Physics 202 Hyche

The three bulbs in Figure Q23.15 are identical. Rank the bulbs from brightest to dimmest. Explain.

(A)> (B=C)

The two circuits in Figure Q22.12 use identical batteries and wires made of the same material and of equal diameters. Rank in order, from largest to smallest, the currents I1,I2,I3I1,I2,I3, and I4I4 at points 1 to 4.

(I1=I2) > (I3=I4)

The wires in Figure Q22.10 are all made of the same material; the length and radius of each wire are noted. Rank in order, from largest to smallest, the resistances R1R1 to R5R5 of these wires. Explain.

(R4) >( R1=R5) > R3 > R2

A parallel-plate capacitor is formed from two 4.0 cm ×4.0 cm4.0 cm ×4.0 cm electrodes spaced 2.0 mm apart. The electric field strength inside the capacitor is 1.0×106 N/C.1.0×106 N/C. What is the charge (in nC) on each electrode?

+14 nC & -14nC

How much energy must be removed from a 200 g block of ice to cool it from 0∘C to −30∘C?

-12.7 kJ

A 1.0-cm-tall object is 10 cm in front of a converging lens that has a 30 cm focal length

-15cm 1.5 cm height

What potential difference is needed to accelerate a He+He+ ion (charge +e+e, mass 4 u) from rest to a speed of 1.0×10^6 m/s?

-21 Kv

Moving a charge from point A, where the potential is 300 V, to point B, where the potential is 150 V, takes 4.5×10−4 J4.5×10−4 J of work. What is the value of the charge?

-3 (Up C)

Two narrow slits are illuminated by light of wavelength λλ. The slits are spaced 20 wavelengths apart. What is the angle, in radians, between the central maximum and the m=1m=1 bright fringe?

.05 Rad

The aurora is caused when electrons and protons, moving in the earth's magnetic field of ≈5.0×10−5 T≈5.0×10−5 T, collide with molecules of the atmosphere and cause them to glow. What is the radius of the circular orbit for An electron with speed 1.0×106 m/s1.0×106 m/s? A proton with speed 5.0×104 m/s5.0×104 m/s?

.114 m 10 m

What magnetic field strength and direction will levitate the 2.0 g wire in Figure P24.33?

.13 T

A 1.5 V D-size battery stores 54 kJ of energy. What steady current could this battery provide for 20 h before being depleted?

.50A

What is the equivalent capacitance of the three capacitors in Figure P23.41?( 20,60,10)

.89 uf

A 20-cm-circumference loop of wire has a resistance of 0.12 Ω0.12 Ω. The loop is placed between the poles of an electromagnet, and a field of 0.55 T is switched on in a time of 15 ms. What is the induced current in the loop

.97 A

A 1.0 kg block is attached to a spring with spring constant 16 N/m. While the block is sitting at rest, a student hits it with a hammer and almost instantaneously gives is speed of 40 cm/s. What are a. The amplitude of the subsequent oscillations? b. The block's speed at the point where x=12Ax=21​A?

0.1m 35 cm/s

Some passengers on an ocean cruise may suffer from motion sickness as the ship rocks back and fourth on the waves. At one position on the ship, passengers experience a vertical motion of amplitude 1 m with a period of 15 s. a. To one significant figure, what is the maximum acceleration of the passengers during this motion? b. What fraction is this of g?

0.2 ms^2 g/50

A 200 g ball is tied to a string. It is pulled to an angle of 8.0° and released to swing as a pendulum. A student with a stopwatch finds that 10 oscillations take 12 s. How long is the string? Mohamed 5.0

0.357

A diffraction grating with 600 lines/mm is illuminated with light of wavelength 500 nm. A very wide viewing screen is 2.0 m behind the granting. a. What is the distance between the two m = 1 fringes? b. How many bright fringes can be seen on the screen?

1.3 7

A current loop in a motor has an area of 0.85 cm20.85 cm2. It carries a 240 mA current in a uniform field of 0.62 T. What is the magnitude of the maximum torque on the current loop?

1.3 X 10^-5

A laser beam in air is incident on a liquid at an angle of 37∘with respect to the normal. The laser beam's angle in the liquid is 26∘. What is the liquid's index of refraction?

1.37

To what potential should you charge a 1.0 μF1.0 μF capacitor to store 1.0 J of energy?

1.41 Kv

How long does it take light to travel through a 3.0-mm thick piece of window glass?

1.5 x 10^-11 s

How much electric potential energy does 1.0 μC1.0 μC of charge gain as it moves from the negative terminal to the positive terminal of a 1.5 V battery

1.5 x 10^-6 J

A solenoid used to produce magnetic fields for research purposes is 2.0 m long, with an inner radius of 30 cm and 1000 turns of wire. When running, the solenoid produces a field of 1.0 T in the center. Given this, how large a current does it carry

1.6 kA

A sinusoidal wave has period 0.20 s and wavelength 2.0 m. What is the wave speed?

10 m/s

What are the magnitude and direction of the electric field at the dot in Figure P21.31

10,000 V/m

An ideal gas at 20∘C consists of 2.2×10^22 atoms. 4.3 J of thermal energy are removed from the gas. What is the new temperature in ∘C?

10.68 degrees celcius

A 5.0-ft-tall girl stands on level ground. the sun is 25∘ above the horizon. How long is her shadow?

10.72 Ft

What is the equivalent resistance of each group of resistors shown in Figure P23.10? (2,3,6)

11 Ohms 9 Ohms

The wave speed on a string is 150 m/s when the tension is 75.0 N. What tension will give a speed of 180 m/s?

110 N

In a typical lightning strike, 2.5 C flows from cloud to ground in 0.20 ms. What is the current during the strike?

12.5KA

An air-track glider is attached to a spring. The glider is pulled to the right and released from rest at t = 0 s. It then oscillates with a period of 2.0 s and a maximum speed of 40 cm/s. a. What is the amplitude of the oscillation? b. What is the glider's position at t = 0.25 s?

12.7 cm 9 cm

What are the strength and direction of the electric field 2.0 cm from a small glass bead that has been charged to +6.0 nC?

135000 N/C away from charge

What is the electric potential at the point indicated with the dot in Figure P21.21 (2.0Nc all 3 corners)

1410V

A potential difference of 53 mV is developed across the ends of a 12.0-cm-long wire as it moves through a 0.27 T uniform magnetic field at a speed of 5.0 m/s. The magnetic field is perpendicular to the axis of the wire. What is the angle between the magnetic field and the wire's velocity?

19 degrees

What is the time constant for the discharge of the capacitor in Figure P23.45? (4,1,1)

2 X 10^-3

Consider one point on an object near a lens. What is the minimum number of rays needed to locate its image point? For each point on the object, how many rays from this point actually strike the lens and refract to the image point?

2 rays Infinity rays

When a guitar string plays the note "A," the string vibrates at 440 Hz. What is the period of the vibration?

2.3 ms

What is the sound intensity of a whisper at a distance of 2.0 m, in W/m2? What is the corresponding sound intensity level in dB?

2.5 X10^-11 W/m2 14 Db

A small plastic sphere with a charge of −5.0 nC−5.0 nC is near another small plastic sphere with a charge of −12 nC.−12 nC. If the spheres repel one another with a force of magnitude 8.2×10−4 N,8.2×10−4 N, what is the distance between the spheres

2.6 cm

Table 24.1 notes that the magnetic field 10 cm from a wire carrying a 1 A current is 2 uT. What is the field 1 cm from the wire?

20 uT

The current through the 30 Ω30 Ω resistor in Figure P23.5 is measured to be 0.25 A. What is the emf εε of the battery?

20V

What is the thinnest film of MgF2(n=1.38) on glass that produces a strong reflection for orange light with a wavelength of 600 nm?

217 nm

A copper block is removed from a 300∘C oven and dropped into 1.00 kg of water at 20.0∘C The water quickly reaches 25.5∘C and then remains at that temperature. What is the mass of the copper block?

218 g

What is the equivalent resistance between points a and b in Figure P23.19? (42,40,45,30)

23.99 ohms

The wave speed on a string under tension is 200 m/s. What is the speed if he tension is doubled?

280 m/s

A 1000 turn coil of wire 2.0 cm in diameter is in a magnetic field that drops from 0.10 T to 0 T in 10 ms. The axis of the coil is parallel to the field. What is the emf of the coil?

3.14 V

A biologist keeps a specimen of his favorite beetle embedded in a cube of polystyrene plastic. The hapless bug appears to be 2.0 cm within the plastic. What is the beetle's actual distance beneath the surface?

3.2 cm

A 10-cm-long wire is pulled along a U-shaped conducting rail in a perpendicular magnetic field. The total resistance of the wire and rail is 0.20 Ω0.20 Ω. Pulling the wire with a force of 1.0 N causes 4.0 W of power to be dissipated in the circuit. What is the speed of the wire when pulled with a force of 1.0 N? What is the strength of the magnetic field?

4 m/s 5T

The length of a steel beam increases by 0.73 mm when its temperature is raised from 22∘C to 35∘. What is the length of the beam at 22∘c

4.7 m

Blue light of wavelength 450 nm passes through a diffraction grating with a slit spacing of 0.001 mm and makes an interference pattern on the wall. How many bright fringes will be seen? A. 1 B. 3 C. 5 D. 7

5

| Figure P22.30 is a current-versus-potential-difference graph for a cylinder. What is the cylinder's resistance?

50 ohms

The intensity of electromagnetic waves from the sun is 1.4kW/m^2 just above the earth's atmosphere. Eighty percent of this reaches the surface at noon on a clear summer day. Suppose you model your back as a 30cm×50cm rectangle. How many joules of solar energy fall on your back as you work on your tan for 1.0 h?

6 X 10^5 J

a. What is the frequency of blue light that has a wavelength of 450 nm? b. What is the frequency of red light that has a wavelength of 650 nm?

6.67 X 10^14 Hz 4.62 X 10^14 Hz

The second minimum in the diffraction pattern of a 0.10-mm-wide slit occurs at 0.70 degrees What is the wavelength of the light?

610 nm

Two 2.0 cm×2.0 cm square aluminum electrodes, spaced 0.50 mm apart, are connected to a 100 V battery. What is the capacitance? What is the charge on the positive electrode

7.08 X 10^-10 Columbs

Helium has the lowest condensation point of any substance; the gas liquefies at 4.2 K. 1.0 L of liquid helium has a mass of 125 g. What is the volume of this amount of helium in gaseous form at STP (1 atm and 0∘C)?

700 L

A motorcyclist is making an electric vest that, when connected to the motorcycle's 12 V battery, will warm her on cold rides. She is using 0.25-mm-diameter copper wire, and she wants a current of 4.0 A in the wire. What length wire must she use?

8.61 m

A parallel-plate capacitor is constructed of two horizontal 12.0-cm-diameter circular plates. A 0.05 g plastic bead, with a charge of −6.0 nC,−6.0 nC, is suspended between the two plates by the force of the electric field between them. Which plate, the upper or the lower, is positively charged? What is the charge on the positive plate?

8.77 x 10^-8 C

A container holds 1.0 g of oxygen at a pressure of 8.0 atm. a. How much heat is required to increase the temperature by 100∘C at constant pressure? b. How much will the temperature increase if this amount of heat energy is transferred to the gas at constant volume?

91.25 J 140 Degrees C

0.10 mol of argon gas is admitted to an evacuated 50cm3 container at 20∘C. The gas then undergoes an isobaric heating to a temperature of 300∘C. a. What is the final volume of the gas? b. Show the process on a pV diagram. Include a proper scale on both axes.

98 cm^3

Two 1.0 kg masses are 1.0 m apart on a frictionless table. Each has +1.0 μC+1.0 μC of charge. What is the magnitude of the electric force on one of the masses? What is the initial acceleration of each mass if they are released and allowed to move?

9X10^-3 N 9x10^-3 m/s^2

A delivery truck with 2.8-m-high aluminum sides is driving west at 75 km/hr in a region where the earth's magnetic field is B = (5.0 x 10^-5 T, north). a) What is the potential difference between the top and the bottom of the truck's side panels? b) Will the tops of the panels be positive or negative relative to the bottoms?

A. 2.917 mV B. the tops will be negative

Which contains the most moles: 10 g of hydrogen gas, 100 g of carbon, or 50 g of lead?

Carbon has the most moles

A person's heart rate is given in beats per minute. Is this a period or a frequency?

Frequency

Which has more mass, a mole of Ne gas or a mole of N2 gas?

Mole of N2 gas

The conducting loop in Figure Q25.11 is moving into the region between the magnetic poles shown. Is the induced current (viewed from above) clockwise or counterclockwise? Is there an attractive magnetic force that tends to pull the loop in, like a magnet pulls on a paper clip? Or do you need to push the loop in against a repulsive force?

Part 1 The induced current in the circuit is in clockwise direction. Part 2 You need to push the loop in against a repulsive force.

A ray of light impinges on a mirror as shown in Figure P18.11. A second mirror is fastened at 90° to the first. After striking both mirrors, at what angle relative to the incoming ray does the outgoing ray emerge?

Part A The angle of emergent ray relative to the incoming ray is 180∘ . Part B The angle relative to incoming ray and outgoing ray is 180∘

A proton moves in a region of uniform magnetic field, as shown in Figure Q24.23. The velocity at one instant is shown. Will the subsequent motion be a clockwise or counterclockwise orbit?

clockwise

Bottlenose dolphins use echolocation pulses with a frequency of about 100 kHz, higher than the frequencies used by most bats. Why might you expect these water-dwelling creatures to use higher echolocation frequencies than bats?

frequency increases with wave speed

The frequency of a light wave in air is 5.3×1014 Hz 5.3×1014 Hz. Is the frequency of this wave higher, lower, or the same after the light enters a piece of glass?

frequency of light will Remain the same

If you want to play a tune on wine glasses, you'll need to adjust the oscillation frequencies by adding water to the glasses. This changes the mass that oscillates (more water means more mass) but not the restoring force, which is determined by the stiffness of the glass itself. If you need to raise the frequency of a particular glass, should you add water or remove water?

remove water

A metal rod A and a metal sphere B, on insulating stands, touch each other as shown in Figure Q20.9. They are originally neutral. A positively charged rod is brought near (but not touching) the far end of A. While the charged rod is still close, A and B are separated. The charged rod is then withdrawn. Is the sphere then positively charged, negatively charged, or neutral? Explain.

sphere is then positively charged

A common trick for opening a stubborn lid on a jar is to run very hot water over the lid for a short time. Explain how this helps to loosen the lid.

the hot water expands the lid

An object is 15 cm in front of a diverging lens with a focal length of −10 cm. Use ray tracing to determine the location of the image. Is the image upright or inverted? Is it real or virtual?

upright and virtual

In Figure Q24.l, suppose the magnet on the right is fixed in place and the magnet on the left is free to pivot about its center. Will the magnet on the left start to rotate? If so, will it initially rotate clockwise or counterclockwise?

The magnet on the left start to rotate in clockwise direction

A positively charged particle is in the center of a parallel-plate capacitor that has charge ±Q±Q on its plates. Suppose the distance between the plates is doubled, with the charged particle remaining in the center. Does the force on this particle increase, decrease, or stay the same? Explain

answer to both blocks, 'not change'