Missed Physics - U World
B.46 D
A patient's eye lens has a focal length of 2 cm. When the patient wears a pair of prescription eyeglasses with an optical power of −4 D, the combined strength of the lenses is approximately: A.42 D B.46 D C.50 D D.54 D
D.multiplying RL by 3. in series: R1 + R2 + R3 = 1,000 + 1,000 + 1,000 = 3,000
Adding two 1,000 Ω resistors in series with RL ( 1,000 Ω)would be equivalent to: A.multiplying RL by 1/3 B.multiplying RL by 2/3 C.multiplying RL by 2. D.multiplying RL by 3.
B.Fluid pressure is not influenced by fluid velocity
Ideal fluids are used to model the behavior of fluids both in motion and at rest. Which one of the following assumptions does NOT apply to an ideal fluid? A.Velocity is equal at all points within a moving fluid. B.Fluid pressure is not influenced by fluid velocity. C.Frictional forces between fluid molecules are negligible. D.The fluid is incompressible
B.II only Because kinetic friction is proportional to the normal force (Fk = μkN), kinetic friction depends on an object's mass. ***** (The coefficient of kinetic friction μk is independent of the size of the contact surface and the speed between the surfaces)
In the experiment, the magnitude of the kinetic frictional force between the ramp and the synthetic skin depends on: I. the area of the contact surface. II. the mass of the load. III. the speed of the synthetic skin. A.I only B.II only C.I and III only D.II and III only
C.0.19
A 10-kg block is suspended in air by a single string that passes through a pulley and is attached on the other side to a 35-kg block that is on the verge of sliding on the ground. What is the coefficient of static friction between the larger block and the ground? (Note: The magnitude of the vertical force the small block exerts on the large block is 87 N.) A.0.11 B.0.15 C.0.19 D.0.23
A.0.42 J/(g⋅°C) q=mc∆T qwater = 50 g (4.2) = 210 c = q/m∆T = -210/(100)(-5) = 210/500 = 0.42 q1 + q2 + q3 + q4 +.... = 0 q1 = - q2 mc∆T(water) + mc∆T(IRON) = 0 50 g (4.2) + (100)c(-5) = 0 210 + (-500)C = 0 200 = 500 C C = 0.42 J
A 100-g block of iron at 31°C is submerged in 50 g of water at 25°C in a thermally insulated container. If the temperature of the system reaches equilibrium at 26°C, what is the specific heat of iron? (Note: The specific heat of water is 4.2 J/(g⋅°C).) A.0.42 J/(g⋅°C) B.1.7 J/(g⋅°C) C.42 J/(g⋅°C) D.170 J/(g⋅°C
A.M∙g∙sin θ Therefore, the frictional force acting on a mass sliding down an incline in dynamic equilibrium is equal in magnitude to the weight of the object multiplied by the sine of the incline angle
A block with mass M slides down an incline of angle θ at constant velocity v. Which of the following expressions is equal to the magnitude of frictional force between the block and the incline? (Note: The acceleration of gravity g = 10 m/s2.) A.M∙g∙sin θ B.M∙g∙cos θ C.M∙g / sin θ D.M∙g / cos θ
C.5.0 N ρalcohol=(specific gravity of alcohol)x (ρwater) ρalcohol=(0.8)(1 kg/L)=0.8 kg/L Fb,alcohol/ Fb,water = ρ,alcohol/ρwater Fb,water = 1 kg/L x 4N / 0.8 kg/L = 5N For an object fully immersed in two different fluids, the ratio of the buoyant forces is equal to the ratio of the fluid densities.***
A bone sample (specific gravity = 3) completely immersed in isopropyl alcohol (specific gravity = 0.8) is subject to a buoyant force of 4 N. What buoyant force would the same bone sample experience when immersed in water? A.2.4 N B.4.0 N C.5.0 N D.12 N
C.15 m/s and 25 m/s draw vectors!!!! 45° is halfway and x and y are equal at 60° the y component is the bigger one!!!!
A cannonball is launched at a speed of 30 m/s and at an angle of 60° above the horizontal. What are the magnitudes of the horizontal and vertical components of the cannonball's initial velocity, respectively? A.5 m/s and 25 m/s B.10 m/s and 15 m/s C.15 m/s and 25 m/s D.25 m/s and 15 m/s
B.70 J total energy = 100 + 10 = 110J KE increases by a factor of 2 squared, 2^2 = 4, so would be 4 x KEinitial KEfinal = 4 x KE = 4 x 10 = 40 J PEfinal=(total energy)−KEfinal PEfinal=110 J−40J=70
A charged particle is accelerated in a uniform electric field. When its velocity is 2 m/s, its electric potential energy is 100 J and its kinetic energy is 10 J. What is the particle's potential energy when its velocity reaches 4 m/s? A.25 J B.70 J C.90 J D.135 J
C.C will increase by 50% C=κ⋅C0
A dielectric material is introduced into the empty space between the two plates of a parallel plate capacitor. How will the capacitance (C) change if the value of the dielectric constant (κ) for the material is 1.5? A.C will decrease by 33%. B.C will not change. C.C will increase by 50% D.C will increase by 100%
C.increasing alveolar pressure. In normal inspiration, the diaphragm contracts to reduce intrapleural pressure, which results in lung expansion. In positive pressure ventilation, an external pump directly increases alveolar pressure by pumping air into the lungs to inflate the lungs.
A positive pressure mechanical ventilator most likely inflates the lungs by directly: A.increasing intrapleural pressure. B.decreasing intrapleural pressure. C.increasing alveolar pressure. D.decreasing alveolar pressure
T = rF x sin(θ) sin = 90 bc perpendicular so = 1*** T = (1.0×10^6 km)⋅(250 N) = 2.5×10^11 N⋅m for direction draw vectors and USE CROSS PRODUCT (r x F). Can see Z is up (positive) *clockwise: the negative direction of the third axis counterclockwise: the positive direction of the third axis
A star orbiting a black hole in a clockwise direction at a radial distance of 1.0 × 10^6 km is acted upon by a counterclockwise friction force of 250 N perpendicular to the orbit radius. What is the torque on the star? A.0 N∙m B.2.5 × 10^9 N∙m in the counterclockwise direction C.2.5 × 10^11 N∙m in the clockwise direction D.2.5 × 10^11 N∙m in the counterclockwise direction
C.50 m
A swimmer enters a straight river at Point A and arrives at Point B downstream on the opposite shore after 80 seconds of swimming. If the river is 30 m wide and flows at a velocity of 0.5 m/s, what is the minimum distance between Points A and B? (Note: Assume the swimmer does not act to oppose the flow of the river.) A.30 m B.40 m C.50 m D.60 m
D.100 J/K Therefore, the amount of heat absorbed by nitrogen is: q = mcΔT q=(2 kg)(2 kJkg⋅K)(5 K)=20 kJ C = q/ΔT = -200kJ/-200K = 0.1 kJ/K 0.1 kJ x 1000 = 100 J/K
A tissue sample at 275 K is submerged in 2 kg of liquid nitrogen at 70 K for cryopreservation. The final temperature of the nitrogen is 75 K. What is the heat capacity of the sample in J/K? (Note: Assume no heat is lost to the surrounding air.) A.0.05 J/K B.0.1 J/K C.50 J/K D.100 J/K
B.50 V electric charge (I) = Q/t I = 0.1/2 = 0.05 A THEN V=IR V = (1,000 Ω) (0.05 A) = 50 V
A voltmeter is placed across RL. If a charge of 0.1 C flows into the input node every 2 s, what will be the reading on the voltmeter? (2 μF capacitor for Cm, a 200 Ω resistor for Rm, and a 1,000 Ω resistor for Rl) A.0 V B.50 V C.100 V D.200 V
D.will increase by 100% Because current is inversely proportional to resistance if the voltage is fixed, reducing the resistance by half will double the current.
An ammeter is added to the circuit as shown. The voltage across the capacitor is kept constant while the frequency is increased from 200 Hz to 400 Hz. Through this change, the value shown by the ammeter: A.will decrease by 50%. B.will not change. C.will increase by 50%. D.will increase by 100%
A.1:1 you can do this :) math mistake
An object is located at a distance of 2 focal lengths from the center of a converging lens. What is the ratio of the height of the image to the height of the object? A.1:1 B.1:2 C.1:3 D.No image is formed
A.The object will sink at a constant velocity. When a downward force is applied to the object, the net force on the object is downward. The object will sink, and its velocity in the downward direction increases with time (accelerates) as described by Newton's second law (F = ma). The moment after the applied force is removed, the net force acting on the object returns to zero (ignoring fluid friction). In the absence of a net force, an object at rest (velocity = 0 m/s) will stay at rest, and an object in motion at a given velocity will stay in motion at the same velocity (Newton's first law)
An object with the same density as water is stationary and suspended in a container filled with water. Ignoring the effects of fluid friction, what will happen to the object after a downward force is momentarily applied? A.The object will sink at a constant velocity. B.The object's downward velocity will increase with time. C.The object will quickly stop sinking. D.The object will sink before returning to its initial position
B.adiabatically. Adiabatic processes, which occur with no heat exchange between the system and the environment.
Based on the passage, a feature of the Joule-Thomson effect is that it occurs: (The temperature change of the gas exiting the valve is described by the Joule-Thomson effect, which occurs without heat transfer with the surroundings) A.isothermally. B.adiabatically. C.isochorically. D.isobarically
D.1.3 × 100 mg/s looking for volume flow rate VFR = linear velocity x cross sectional area (10m/s) x (pi(.2^2)) = 0.4 x pi = 1.3cm^3/s = 1.3 mg/s
Blood flows through a vessel in the leg at an average velocity of 10 cm/s. How much glucose passes by a segment of the blood vessel each second if the radius of the blood vessel is 0.20 cm and each 1.0 cm3 of blood contains 1.0 mg of dissolved glucose? A.4.0 × 10−1 mg/s B.4.0 × 100 mg/s C.1.3 × 10−1 mg/s D.1.3 × 100 mg/s
B.the thermal conductivity of the tile is higher than the thermal conductivity of the carpet. high thermal conductivity = fast transfer of energy -colder objects feel very cold bc they steal our heat fast -hot objects feel very hot because they transfer heat to you quickly
Different substances have different thermal conductivities k, which measure how well heat is transferred by molecular collisions. The heat flow rate per unit area H is defined by: where ΔT is the difference in temperature over a distance L. The tiled part of a floor in a room feels colder than the carpeted part because: A.the temperature of the tile is lower than the temperature of the carpet. B.the thermal conductivity of the tile is higher than the thermal conductivity of the carpet. C.the thermal conductivity of the tile is lower than the thermal conductivity of the carpet. D.heat travels a greater distance through the carpet
B.The temperature of the water would begin to increase at a later time. The temperature of the water will be constant at 0°C as long as ice is still present and will not start to increase until after all the ice melts. The latent heat of fusion (melting) is the amount of heat (energy) required to convert a solid at its melting point temperature to its liquid phase by breaking the bonds between the molecules in the solid phase
If the student repeated the experiment by replacing the water in the calorimetry device with an ice bath at 0°C, how would the experimental results differ? A.The temperature of the water would increase to 10°C. B.The temperature of the water would begin to increase at a later time. C.The heat released when ice melts increases the measured temperature. D.The amount of heat released from the combustion reaction would increase.
C=κ⋅C0 **Use graph for concentration and dielectric constants C10 mM=1.2⋅C0 C2.5 mM=1.0⋅C0 % difference=(C2.5 mM−C10 mM) / C10 mM×100% % difference=(1.0⋅C0−1.2⋅C0)/ 1.2⋅C0×100% % difference= −0.2⋅C0 / 1.2⋅C0 ×100=−17%
Suppose that a 5-mL blood sample with a glucose concentration of 10 mM has capacitance C. How will C change if the concentration of blood glucose is reduced to 2.5 mM? A.C will decrease by approximately 20%. B.C will remain the same. C.C will increase by approximately 20%. D.C will increase by approximately 40%
C.are excessively refracted at the lens periphery. a perfectly spherical non-ideal lens produced multiple focal points -this can be fixed by altering the thickness at the periphery -abberation causes more extreme changes at the periphery, so that the area must be adjusted to lessen its impact Because reducing the thickness of the lens periphery will lead to less refraction of light, light rays exiting the periphery of a spherical converging lens can be said to refract excessively, converging on a focal point that is too close to the lens.
That the spherical aberration of a converging lens is corrected by reducing the thickness of the lens periphery means that the light rays emerging from aberrant converging lenses: A.are insufficiently refracted at the lens periphery. B.converge at the lens focal point uniformly. C.are excessively refracted at the lens periphery. D.are scattered due to chromatic dispersion
B.an electrical insulator
The misdirected transmission of a high-voltage electrical current is associated with a risk of accidental fire. To eliminate the risk of such accidents, the type of material that must be applied to the surface of bare wires is known as: A.an electrical conductor. B.an electrical insulator C.a thermal conductor. D.a thermal insulator.
A.25 J AREA, rectangle + triangle
The relationship between the length of a spring and the force required to stretch the spring is shown below. What is the work done when the spring length is increased from 20 cm to 30 cm? A.25 J B.35 J C.250 J D.350 J
A.2.5 × 10−9 J U=1/2(CV^2) C = 2 x 10^-6 V = 50mv x 10^-3 = 5 x 10^-2 U = 1/2 ( 2 x 10^-6) (5 x 10^-2)^2 = 2.5 x 10^-9
To test the integrity of the capacitor, researchers maintained a voltage of 50 mV across the parallel portion of the circuit for several minutes. During this time, how much energy was stored in the capacitor? (2 μF capacitor for CM, a 200 Ω resistor for RM, and a 1,000 Ω resistor for RL) A.2.5 × 10−9 J B.5.0 × 10−9 J C.5.0 × 10−8 J D.1.0 × 10−7 J
B.the elasticity of pulmonary tissue. pulmonary resiliency allows for passive expiration and does not require muscles or ATP energy, and can therefore occur under the paralytic effects of anesthesia.** (A is wrong the Venturi effect is irrelevant to the pressure in the alveoli and lung exhalation)
Unassisted expiration is possible under the effects of anesthesia due to: A.pressure build-up due to the Venturi effect B.the elasticity of pulmonary tissue. C.turbulent flow at high positive pressures D.energy stored in the diaphragm
A.Mass of the head Power = W/t W = change in kinetic energy Therefore, the mass of the head is needed in addition to the given information to determine the power of the collision. (final velocity can be calculated from figure 2!!!!)
What additional information do the researchers need from the crash test dummy to estimate the power of the collision in the experiment shown in Figure 2? A.Mass of the head B.Time until the head stops moving C.Tension of the neck during the collision D.Velocity of the head at the end of the collision
A.sin 50°/sin 35° **asking to solve for n2 n2=sin 50/°sin 35°
What is the camera lens' refractive index if incident light 50° from the normal is refracted to 35° from the normal? A.sin 50°/sin 35° B.sin 35°/sin 50° C.1/sin 50°[1%] D.1/sin 35
D.6.4 × 10^−16 N F=qE doubly ionized particle will be twice the charge of an electron (1.6 × 10−19)**: 2q q=2(1.6×10^−19 C)=3.2×10^−19 C F=(3.2×10^−19 C)(2,000 NC)=6.4×10^−16 N
What is the force felt by a doubly ionized particle in a 2,000-N/C electric field? (Note: The charge of an electron is e = 1.6 × 10−19 C.) A.1.6 × 10^−22 N B.3.2 × 10^−22 N C.3.2 × 10^−16 N D.6.4 × 10^−16 N
B.7 × 105 N/m2 *Chris help with unit conversion
What is the maximum pressure in N/m2 generated by skeletal muscles? A.7 × 103 N/m2 B.7 × 105 N/m2 C.7 × 106 N/m2 D.7 × 109 N/m2
B. 2 × 10^−7 s
What is the period of an ultrasound signal that is attenuated by 20 dB after it travels 4 cm into soft tissue? A.5 × 10^−9 s B.2 × 10^−7 s C.5 × 10^−6 s D.2 × 10^−4 s
A.decreases because the weight component perpendicular to the ramp decreases. ***Kinetic friction is proportional to the normal force For an object on a ramp, the normal force is due to the object's weight. As the angle of inclination increases, the normal force decreases; therefore, kinetic friction decreases.
When the angle of inclination of the ramp increases, kinetic friction: A.decreases because the weight component perpendicular to the ramp decreases. B.decreases because the weight component parallel to the ramp decreases. C.increases because the weight component perpendicular to the ramp increases. D.increases because the weight component parallel to the ramp increases.
B.The voltage drops across RB and RE are equal because the resistors are in parallel. if in parallel, same voltage drop!
Which of the following statements best describes the behavior of the circuit in Figure 1 when the fully charged capacitor (comprising red blood cells) is discharged? A.The electric currents through RB and RE are equal because the resistors are in series. B.The voltage drops across RB and RE are equal because the resistors are in parallel. C.The electric current through RB exceeds that through RE because the capacitor is fully charged. D.Both the current and voltage drop across RB and RE are equal because the same power source is used
B.The image will shift closer to the eye's lens far sighted = can't see near = image behind retina ***need converging lens to bring image forward.
Which of the following will occur if a corrective lens is placed in front of an eye that is unable to form a clear image of a nearby object? A.The image will shift away from the eye's lens. B.The image will shift closer to the eye's lens. C.Spherical aberration will increase. D.Optical power will decrease
C.400 N As a result, the tension on lumbar disc 1 is equal to approximately half the volunteer's body weight: T=Mg/2=(80 kg)(10 m/s2)/ 2=400 N **tension on lumbar disk would be equivalent to the amount of his weight that is below it since it must hold that portion up and will be roughly half
A volunteer with a mass of 80 kg is suspended by his arms on Earth. What is the approximate tension on lumbar disc 1? (Note: The acceleration of gravity is g = 10 m/s2) A.40 N B.70 N C.400 N D.700 N
B.Astronaut center of mass. In microgravity, PFS is observed as extracellular fluid previously contained within lower portions of the body (ie, feet and legs) shifts to the upper portions of the body (ie, chest and head). Consequently, the shift in an individual's fluid mass will result in a shift in the individual's center of mass.
According to the passage, which of the following changes as an astronaut leaves Earth's surface and enters orbit? A.Magnitude of kinetic friction between the astronaut and nearby objects. B.Astronaut center of mass. C.Astronaut bodily inertia. D.Magnitude of the gravitational force between the astronaut and the spacecraft
B.−1 m/s2 **use coefficient of kinetic friction b/c moving (Because friction opposes sliding, kinetic friction causes sliding objects to decelerate so negative acceleration) F = -μkmg a=Fnet/m = -μkmg/m = -μkg a = - (0.1) (10) = -1 m/s^2
After the load leaves the ramp, it slides on a horizontal table with a coefficient of kinetic friction μk of 0.1 and a coefficient of static friction μs of 0.3. If the direction of the load's velocity is positive, what is the acceleration of the load? (Note: Use g = 10 m/s2.) A.−3 m/s2 B.−1 m/s2 C.1 m/s2 D.3 m/s2
C.successive sound waveforms are emitted further away from the observer. **Lower doppler frequency is due to increased distance between waveforms, leading to a lower perceived frequency, since speed is unchanged *intensity is related to volume, not pitch
An observer perceives a sound to be lower in frequency when the sound source is moving away from the observer. This shift in the frequency of the perceived sound occurs because: A.the sound waveform velocity decreases as the distance between source and observer increases. B.sound waveforms are reflected off environmental objects nearby. C.successive sound waveforms are emitted further away from the observer. D.the sound wave intensity decreases as the distance between source and observer increases
B.20 kJ q = mc∆T = 500 (1) (10) = 5,000 cal q = 5,000 cal (4.2 kJ/1,000 calories) = 21 kJ
Approximately how much heat in kJ was released from the combustion of the 1-g sample? A.5 kJ B.20 kJ C.40 kJ D.70 kJ
C.1.4 A The capacitor's resistance RC is found from Figure 2. At 200 Hz, the capacitor's resistance Rc = 400 Ω. The current through the capacitor is given as Ic = 0.7 A, and the resistor's resistance is given as Rm = 200 Ω. Therefore, the current through the resistor can be calculated: ImRm=IcRc Im = Rc/Rm (Ic) = (400/200) x (0.7) = 2 x 0.7 = 1.4 A
At 200 Hz, the current in CM is 0.7 A. What is the current in RM? A.0.35 A B.0.70 A C.1.4 A D.2.8 A
D.a higher voltage difference across the body. V = IR, hight body fat (high resistance) would equal high voltage between the two points***
Fatty tissue has a lower electrical conductivity than lean (non-fat) tissue. This property allows body fat content to be estimated by modeling the tissue between two points as a single resistor. For the same amount of current entering the body, relatively high body fat content would be indicated by: A.an increased current leaving the body. B.a decreased current leaving the body. C.a lower voltage difference across the body. D.a higher voltage difference across the body.
C.it increases the normal force. The maximum value of static friction is proportional to the normal force, which is the perpendicular force one surface exerts on the other. Therefore, greater stretching of skin creates a greater normal force around a cannula and greater static friction to better prevent slipping
For equally sized trocar-cannula systems, incisions made for blunt-tipped trocars are smaller than those made by sharp-tipped trocars, forcing the skin to stretch more around the cannula. This option better prevents slipping after the cannula is inserted because: A.it decreases the contact surface area. B.it decreases the static friction. C.it increases the normal force. D.it increases the coefficient of static friction
D.400 m/s2 d=v0t + 1/2at^2 d = 2 m, t = 0.1 s: 2 = 1/2 a (0.1)^2 a = =400 m/s2
In one experimental trial, the projectile was uniformly accelerated from rest to a distance of 2 m in 0.1 s. What was the acceleration of the projectile? A.20 m/s2 B.40 m/s2 C.200 m/s2 D.400 m/s2
B.Particle B Specifically, particle B experiences three forces: a repulsive electric force from particle A (FAB) and attractive electric forces from both particle C (FBC) and particle D (FBD). Each of the forces acting on particle B is oriented along the same line toward particles C and D (ie, to the right). Furthermore, FAB has the largest magnitude in this setup because the charges of particles A and B (+4q and +3q, respectively) are relatively large and the distance between particles A and B (rAB) is relatively small. Consequently, the sum of electric forces acting on particle B is the largest in magnitude such that particle B accelerates most rapidly once the charges are released.
Four charged particles of equal mass are initially fixed in place along a straight line, as shown above. If all the charged particles are released at the same time, which particle would initially accelerate most rapidly? A.Particle A B.Particle B C.Particle C D.Particle D
B.2 cm For each 10-fold decrease, sound intensity decreases by 10 dB. Therefore, a 100-fold decrease in sound intensity corresponds to a decrease by 20 dB.
How much farther will a 5 MHz signal penetrate compared to a 10 MHz signal when the initial intensity of each signal decreases by a factor of 100? A.1 cm B.2 cm C.4 cm D.10 cm
C.I and II only electromagnetic radiation has *constant* VELOCITY (3 x10^8), therefore only wavelength and frequency can change (III. wrong) C = λ x f, as wavelength increases, frequency decreases (I - correct) point of origin for a light wave would be tracing it straight back from the trajectory it arrives so (II- correct)
If one gamma photon out of a pair is Compton-scattered within the patient (not at the detector) and both gamma photons are still detected, which of the following would be seen? I. The frequency of the scattered photon would be lower. II. The point of origin would appear to be at a different location. III. The velocity of the photon would decrease. A.II only B.III only C.I and II only D.I and III only
B.2/3E **identify trends first at 60°, wavelength goes up therefore energy must GO DOWN (C and D wrong) **if you look at graph very closely you can see its more than 50%
If the angle between a Compton-scattered photon and an electron is 60°, what is the energy of the scattered photon in terms of the original energy E? A.1/2E B.2/3E C.E D. 3/2E
B.6,300 mL/min volumetric flow rate is EQUAL to cardiac output = stroke volume x heart rate STEP ONE: find stroke volume (use graph) 120 mL - 50 mL = 70mL STEP TWO: find heart rate- cycles/min (1.5 cycles/1 min) x (60 s/1min) = 90 cycles/min CALCULATE volumetric flow rate: 70 x 90 = 6,300mL/min
If the pulsatile-flow LVAD in Figure 2 pumps with a frequency of 1.5 Hz, what is the volumetric flow rate of blood throughout the systemic circulatory system? A.2,800 mL/min B.6,300 mL/min C.9,900 mL/min D.10,800 mL/min
A.45/π cm/s use cardiac output** 1. ∆P = CO x VR CO = ∆P/VR = 45 mm Hg / 1 mm Hg⋅s⋅mL−1 = 45 mL/s **1mL = 1cm^3 2. CO = cross sectional area x velocity 45cm^3/s = π(cm^2) x velocity velocity = 45 cm/ πs
If the radius of the outflow tube is 1 cm and the LVAD pump generates a pressure of 45 mm Hg, what is the velocity of blood through the outflow tube if peripheral resistance is 1 mm Hg⋅s⋅mL−1? A.45/π cm/s B.45/π cm3/s C.45 cm/s D.45 cm3/s
A.20 mW, released as heat According to graph, the resistance at 400Hz is 200 Ω Power = V^2 / R = (2V)^2 / 200 = 400 / 200 = 0.02 W
If the voltage across the parallel portion of the circuit is 2 V, how much power is dissipated from CM at 400 Hz? A.20 mW, released as heat B.20 mW, stopping the flow of current C.800 mW, released as heat D.800 mW, stopping the flow of current
B.0.10 mechanical advantage=Fo/ Fi = di/ do di/do=3 cm / 30 cm=0.1 the force that the bicep applies must be greater than the downward force of the ball since the ball is far from the fulcrum *since the bicep is far its force must be 10 times higher, so it's advantage is 0.1
Ignoring the weight of the arm, what is the mechanical advantage of the biceps when it is lifting a ball in Experiment 2? A.0.07 B.0.10 C.10 D.15
C.It is 1,000 times less intense. 20 dB - 50 dB= −30 dB** A sound that is 30 dB lower is 10^3 = 1,000 times less intense
In Figure 2, how does the hearing threshold intensity at 1,500 Hz compare to the threshold intensity at 2,000 Hz? A.It is 30 times less intense. B.It is 30 times more intense. C.It is 1,000 times less intense. D.It is 1,000 times more intense
A.perpendicular to both the ion's velocity and the direction of the magnetic field. magnetic force is perpendicular to both the ion's velocity v and the direction of the magnetic field B.***
In the MS-MS separation chamber, the direction of the magnetic force on a moving ion is: A.perpendicular to both the ion's velocity and the direction of the magnetic field. B.perpendicular to the ion's velocity and parallel to the direction of the magnetic field. C.parallel to both the ion's velocity and the direction of the magnetic field. D.parallel to the ion's velocity and perpendicular to the direction of the magnetic field
D.D *always consider mass when comparing protons and electrons (since electrons are much lighter, they will experience a higher magnitude of acceleration and turn in a tighter circle)
In the presence of an external magnetic field (not shown), a proton initially traveling upward is deflected into the path labeled as A in the following figure. What would be the expected path for an electron in the same magnetic field? A.A B.B C.C D.D
C.Running a combustion engine The energy released from combustion is transformed into several forms. The combustion event produces a flash of light and a loud sound. The temperature of the gases increases (thermal energy), and the gases expand to move the engine's components (kinetic energy). Therefore, the conversion from chemical energy to thermal and kinetic energy takes place during the operation of a combustion engine**
In which of the following processes does energy convert from chemical energy to thermal and kinetic energy? A.Digesting a piece of bread B.Toasting a piece of bread C.Running a combustion engine D.Powering a motor with a battery
A.smaller. Because the speed of light is much greater than the speed of sound, the observed frequency shift will be smaller for laser Doppler flowmetry. ∆f/f=v/c Doppler shift is inversely related to the speed of the wave.** (The speed of sound in blood is given in the passage as c = 1,570 m/s. Speed of light speed of light c = 3 × 108 m/s.)
Laser Doppler flowmetry uses an infrared laser to measure blood flow velocity. Compared to ultrasound, the observed frequency shift using this technique is: (The speed of sound in blood is given in the passage as c = 1,570 m/s. ) A.smaller. B.the same. C.larger. D.zero.
C.I and III only the given observed frequency of 6 × 1014 Hz occurs when there is no Doppler shift; the chest is stationary, and its velocity is zero which is where slope is zero (I and III)
Laser Doppler vibrometers detect the Doppler shift of a laser beam reflected off an individual's chest to measure respiratory rate. The calculated displacement of the chest during a breath using a 500-nm laser is shown below. If the laser source is stationary, at which point(s) would the observed frequency of the reflected laser be 6 × 1014 Hz? A.II only B.I and II only C.I and III only D.II and III only
D.creates droplets with smaller surface areas because high surface tension indicates high cohesive forces, water with greater surface tension creates droplets with smaller surface areas (. Therefore, water with greater surface tension will have stronger van der Waals forces)
Many inhalational anesthetics are thought to increase surface tension effects in the alveoli. Water with greater surface tension: A.climbs farther in a narrow glass tube. B.evaporates more quickly. C.has weaker van der Waals forces. D.creates droplets with smaller surface areas
A.be hotter than the matter orbiting stars. Energy of X-rays > Energy of infrared rats Radiation energy is directly related to the temperature of the object that emits the radiation. Hotter objects radiate waves in the higher frequency region of the spectrum; conversely, colder objects radiate waves in the lower frequency region. since the matter orbiting black holes emits x-rays, which have a higher frequency and a higher energy than the infrared radiation emitted by matter orbiting stars, the temperature of the matter orbiting black holes must be greater than the temperature of the matter orbiting the stars.
Matter falling in the gravitational field of a central mass can form a hot, charged fluid. The fluid matter orbiting some stars radiates infrared light, but the matter orbiting black holes emits x-rays. Which of the following explains this discrepancy? The matter orbiting black holes must: A.be hotter than the matter orbiting stars. B.be colder than the matter orbiting stars. C.have lower kinetic energy than the matter orbiting stars. D.exhibit higher viscosity than the matter orbiting stars.
D.1,500 W 1 hp = P = mgΔh/t = (75 kg)(10m/s^2)(1m)/1s = 750 W 2 hp = 2p = 2 x 750 = 1,500W
One horsepower (hp) is the amount of power required to lift a 75-kg mass a vertical distance of 1 m in 1 s. What is 2 hp equivalent to in watts (W)? A.75 W B.150 W C.750 W D.1,500 W
A.rapidly expanding and contracting. The rapid expansion and contraction of crystals creates pressure waves (sound) by vibrating nearby particles. Sound is propagated in the form of pressure waves by the vibrations of the molecules in a medium **SOUND
Piezoelectric crystals likely create sound by: A.rapidly expanding and contracting. B.emitting high-energy photons. C.generating heat waves. D.sending pulses of electricity
D.decrease by a factor of 4. pay attention** asking about the original!! Therefore, replacing the original resistor with another that has ¼ the conductivity (4 times the resistance and resistivity) of the original will decrease the current traveling through the circuit to ¼ its original value
Suppose that a simple circuit comprising one voltage source and one metallic resistor yields current I. If the resistor were replaced with another resistor that is identical except that it has 75% lower conductivity, then I would: A.increase by a factor of 2. B.increase by a factor of 4. C.decrease by a factor of 2. D.decrease by a factor of 4.
B.TBI and no skull fracture a = V2-V1/t2-t1 = 10/(1 x 10^-3) = 1000 = acceleration **take that to figure 1: at an acceleration of 1,0000 we are above the TBI close, but below TBI open so we get the TBI, but not the skull fracture
Suppose the physical characteristics of the crash test dummy accurately represent those of a human. What is the expected injury of the impact shown in Figure 2 if the head accelerated to 10 m/s at the end of the impact? A.No injury B.TBI and no skull fracture C.Skull fracture and no TBI D.TBI and skull fracture
C.700 N **TREAT IT LIKE A FULCRUM Therefore, the torque due the biceps (B) is equal to the sum of the torques due to the weight of lower arm (A) and the ball's mass (M): Tb= Ta + Tm
Suppose the subject is holding a 4-kg ball during Experiment 1. Ignoring friction, what is the force exerted by the biceps? (Note: Use g = 10 m/s2.) (The estimated weight of the subject's lower arm is 45 N, and the subject's lower arm segments to the elbow are shown in Table 1.) A.85 N B.340 N C.700 N D.2,100 N
**USE GRAPH, Vintitial = 101 a̅ =ΔV/ΔT =Vf−Vi / Tf−Ti = 61 - 101 /600 ms = -67.0
The blood leaving the aorta reaches the circle of Willis, a collection of arteries that supplies blood to the brain. Assume that it takes 600 ms for blood to reach the circle of Willis and that its average velocity is reduced to 61 cm/s. What is the average acceleration experienced by the blood? A.−67.0 cm/s2 B.−0.670 cm/s2 C.0.670 cm/s2 D.67.0 cm/s2
C.The bomb cell is a closed system, and the calorimetry device is an isolated system.
The bomb cell and the calorimetry device used in the experiment are what types of thermodynamic systems? A.Both are closed systems. B.Both are isolated systems. C.The bomb cell is a closed system, and the calorimetry device is an isolated system. D.The bomb cell is an isolated system, and the calorimetry device is a closed system.
D.4 times as large. A1v1=A2v2 (A = πr^2)
The diameter of a segment of an artery is reduced by a factor of two due to an obstruction. Assume that the flow is incompressible and laminar. Compared to an unobstructed segment of the artery, the velocity of blood in the obstructed segment of the artery is: A.1/4 as large B.1/2 as large. C.2 times as large. D.4 times as large.
C.25 mm pipe length (pipe open at both ends): L = λ/2 FIND WAVELENGTH **Therefore, the resonant wavelength is twice the given length L = 0.25 m of the stethoscope: λ=2L=2(0.25 m)=0.5 m F = v/λ= 350 / 0.5 m = 700 Hz From Figure 1, a frequency of 700 Hz would cause the basilar membrane to resonate around 25 mm from it base.
The earliest stethoscope was simply a wooden pipe open at both ends. The fundamental frequency of a 0.25-m stethoscope will cause resonance at approximately what distance along the basilar membrane from its base? (Note: Use 350 m/s for the speed of sound in air.) (The stethoscope is described as a pipe open at both ends**) A.7 mm B.16 mm C.25 mm D.32 mm
C.It increases. Furthermore, the conservation of energy dictates that the energy absorbed by an electron must contribute to either the ejection of the electron (overcoming the work function) or to the kinetic energy of the electron following ejection: hf=1/2mv^2+ W Consequently, increasing the energy of electromagnetic radiation (ie, frequency) beyond the value of the work function will increase the kinetic energy of ejected electrons.
The photoelectric effect refers to the ejection of electrons from a material when the material absorbs electromagnetic radiation of sufficient energy. As the frequency of electromagnetic radiation increases, what happens to the kinetic energy of ejected electrons? A.It decreases. B.It remains constant. C.It increases. D.It changes but is not dependent on the energy of electromagnetic radiation
B.1:2 Tension force T1 acts on the portion of the rope attaching pulley B to the ceiling, while tension force T2 acts on the portion of the rope between pulley B and the user such that: Foriginal = T2 = W2 As a result, the inclusion of pulley B within the system yields a mechanical advantage of two. Consequently, removing pulley B from the system will double the magnitude of force required to support the weight of the mass. Fnew=2⋅Foriginal = W
The suspension of mass M within a two-pulley system requires a force F. If pulley B is removed from the system, what is the ratio of the original value of the force with two pulleys to the new value of the force with one pulley? A.1:1 B.1:2 C.1:3 D.1:4
D.(RE ∙ RD)/(RE + RD)
To simplify calculations, mathematical models of DSGR can be generated that replace RE and RD in Figure 1 with an equivalent resistor Req. The mathematical expression for Req is: A.RE + RD B.RE ∙ RD C.(RE + RD)/(RE ∙ RD) D.(RE ∙ RD)/(RE + RD)
A.the inertia of the brain. A contrecoup injury is described in the passage as a brain injury that occurs on the side of the head opposite an impact. This form of brain injury involves the movement of the brain relative to the skull due to the rapid acceleration and deceleration of the head. Because the brain can move within the skull, the brain will continue to move due to its inertia even after the skull had slowed significantly or stopped. Due to the brain's inertia, the brain can continue to move independently of the skull and result in a contrecoup injury.**
When a stationary head is hit by a moving projectile, a contrecoup injury is likely to occur due to: A.the inertia of the brain. B.the weight of the skull. C.the center of mass of the head. D.the potential energy of the projectile
B.The arterioles, because they experience the largest pressure drop ΔP = Q × R ***pressure is directly proportional to its resistance (R) so greatest pressure drop across its entire length has the greatest resistance and is the main source of peripheral resistance
Which group of blood vessels is the main source of peripheral resistance? A.The arteries, because they cause the greatest pressure fluctuations B.The arterioles, because they experience the largest pressure drop C.The capillaries, because they have the smallest vessel radii D.The venules, because they decrease blood pressure to its minimum
B.Eradio < Emicrowave < Evisible Write it out, Evisible = ROYGBIV
Which of the following expressions correctly compares the energies of visible light (Evisible), microwaves (Emicrowave), and radio waves (Eradio)? A.Eradio = Emicrowave < Evisible B.Eradio < Emicrowave < Evisible C.Emicrowave > Eradio > Evisible D.Eradio = Emicrowave > Evisible
C.(F)(2L) W = F x d d = depends on the TOTAL distance through which the force is applied ***bc friction is a nonconservative force (not displacement)
Which of the following expressions gives the magnitude of the work done by the frictional force F if the synthetic skin slides down the entire length L of the ramp and then is pushed back up to its original position? A.0 B.(F)(L) C.(F)(2L) D.(F)(3L)
C. as blood passes along the capillary in the alveoli, it will increase in partial pressure of anything that is extracting from the alveoli
Which of the following graphs best depicts the anesthetic partial pressure along the length of the pulmonary capillaries when it is first administered?
A. torque = f x distance torque will increase as distance increases so A
Which of the following graphs shows the relationship between the torque generated by the weight of the ball and the angle the biceps makes with the lower arm in Experiment 2?
A. Entropy of nitrogen, because it describes an equilibrium state of the system A system's entropy is a measure of its current state of disorder and does not depend on how the system arrived at that state. Therefore, the entropy of nitrogen is a state function work is a process function because it describes what was done to the system to change its state. Although it is true that the work done by the compressor describes a path to an equilibrium state, work does not describe the state of the system. Therefore, work is a process function, not a state function.
Which thermodynamic quantity involved in the Hampson-Linde cycle is a state function? A.Entropy of nitrogen, because it describes an equilibrium state of the system B.Entropy of nitrogen, because it describes a path to an equilibrium state of the system[20%] C.Work done by the compressor, because it describes an equilibrium state of the system[11%] D.Work done by the compressor, because it describes a path to an equilibrium state of the system
