Physics 1401 Final
The two forces indicated in Figure above act on a 3.00 kg object. What is the acceleration of the object?
(1.67 m/s^2)X - (0.333 m/s^2)y
The weather outside is frightful. The temperature is -22 F. What is the corresponding temperature in the Celsius scale?
-30 C
The moment of inertia of a uniform rod (about its center) is given by I = ML^2/12. What is the kinetic energy of a 120-cm rod with a mass of 450 g rotating about its center at 3.60 rad/s?
.350 J
The sum of two vectors has the greatest magnitude where angle between these two vectors is
0 degrees
A 320-g mass and a 400-g mass are attached to the two ends of a string that does over a pulley with a radius of 8.70 cm. Because of friction, the pulley does not begin to rotate. What is the magnitude of the frictional torque on the bearing of the pulley if the system is in static equilibrium?
0.00683 Nm
a 320-g air track cart traveling at 1.25 m/s collides elastically with a stationary 270-g cart. What is the speed of the 320-g cart after the collision?
0.106 m/s
Jennifer hits a stationary 200 gram ball and it leaves the racket at 40 m/s. If time lapse photography shows that the ball was in contact with the racket for 40 ms: (a) What average force was exerted on the racket? (b) What is the ratio of this force to the weight of the ball?
0.20 kN, 1.0x10^2
How much work is required to stretch a spring 25.2 cm if its force constant is 12.3 N/m?
0.391 J
A 1000-kg helicopter hovers over a forest fire and starts to squirt water downward with a speed of 10 m/s at a rate of 40 kg/s. What is the initial upward acceleration on the helicopter when it first starts to release the water?
0.40 m/s^2
What is the length of a simple pendulum with a period of 2.00s?
0.994 m
The deepest point of the Pacific Ocean is 11,033 m, in the Mariana Trench. What is the water pressure at that point? The density of seawater is 1025 kg/m^3
1.11x10^8 Pa
The coefficient of linear expansion of steel is 12 x 10^-6 K^-1. What is the change in length of a 25 m steel bridge span when it undergoes a temperature change of 40 K?
1.2 cm
The coefficient of linear expansion of steel is 12 x 10^-6 K^-1. What is the change in length of a 25-m steel bridge span when it undergoes a temperature change of 40K?
1.2 cm
A mass of 375 g hangs from a string that is wrapped around the circumference of a pulley with a moment of inertia of 0.0125 kgm^2 and a radius of 26.0 cm. When the mass is released, the mass accelerates downward and the pulley rotates about its axis as the string unwinds. What is the tension in the string?
1.21 N
A flatbed truck is carrying a 20.0 kg crate up a sloping road inclined 15.0 degrees above the horizontal. The coefficient of static friction between the crate and the bed is 0.400. What is the maximum acceleration that the truck can have if the crate is to stay in place?
1.25 m/s^2
In a particle accelerator, a proton reaches an acceleration of 9.0 x 10^13 m/s^2. The mass of a proton is 1.7 x 10^-27 kg. What is the force on the proton?
1.53x10^-13
Figure above represents the velocity of a particle as it travels along the x-axis. What is the average acceleration of the particle between t=1 seconds and t=4 seconds?
1.7 m/s^2
An object hits a wall and bounces back with half of its original speed. What is the ratio of the final kinetic energy to the initial kinetic energy?
1/4
Three boxes rest side-by-side on a smooth, horizontal floor. Their masses are 5.0 kg, 3.0 kg, and 2.0 kg, with the 3.0 kg mass in the center. A force of 50 N pushes on the 5.0 kg mass, which pushes against the other two masses. What is the contact force between the 5.0 kg mass and the 3.0 kg mass?
10 N
To determine the height of a flagpole, Abby throws a ball straight up and times it. She sees that the ball goes by the top of the pole after 0.5 s and then reaches the top of the pole again after a total elapsed time of 4.1s. How high is the pole above the point where the ball was launched?
10 m
A harmonic wave has a wavelength of 2.0 m and a frequency of 5.0 Hz. What is the speed of the wave?
10 m/s
Refer to Figure above. If you start from the Bakery, travel to the Cafe, and then to the Art Gallery, what is the distance you have traveled?
10.5 km
Neptune has a radius of 2.48 x 10^7 m and an escape velocity of 23,000 m/s. What is the mass of Neptune? G = 6.67 x 10^-11 Nm^2/kg^2
101 X 10^26 kg
A projectile is shot from the edge of a vertical cliff 60.0m above the ocean. It has a speed of 100 m/s and is fired at an angle of 35.0 degrees above the horizontal. How far from the foot of the vertical cliff does the projectile hit the water?
1080 m
How many cm^2 equal a m^2
10^2
A 20.0 gram mass is attached to a 120 cm long string as shown in Figure above. The tension in the spring is measured to be 0.200 N. What is the angle a?
11.2 Degree
An astronaut stands by the rim of a crater on the moon, where the acceleration for gravity is 1.62 m/s^2 To determine the depth of the crater, she drops a rock and measures the time it takes for it to hit the bottom. If the depth of the crater is 120 m, how long does it take for the rock to fall?
12.2 s
You drop a stone down a well. You hear the splash 1.63 s later. How deep is the well? The speed of sound in air is 343 m/s.
12.5 m
The position of a mass that is oscillating on a spring is given by x=(12.3cm) cos[(1.26 s^-1)t]. What is the speed of the mass when t=0.805s?
13.2 cm/s
A vertical cylindrical cylinder, closed at the bottom end, is fitted at the top with a piston, which can move freely. The mass of the piston is 10.0 kg and the initial height of the piston above the bottom of the cylinder is 25 cm. A mass of 8 kg is placed on the piston, assuming that the temperature is kept constant?
14 cm
A 30.0 kg load is being lifted with constant speed using the ideal pulley arrangement shown in Figure above. What is the magnitude of the force F?
147 N
A figure skater is spinning slowly with arms outstretched. She brings her arms in close to her body and her moment of inertia decreases by 1/2. Her angular speed increases by a factor of
2
The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s respectively. How long does it take for the football to rise to the highest point of its trajectory?
2.0 s
An airplane is flying at a speed of 200 m/s in level flight at an altitude of 800 m. A package is to be dropped from the airplane to land on a target on the ground. At what horizontal distance away from the target should the package be released so that it lands on the target?
2.55 km
How much heat must be removed from 456 g of water at 25.0 C to change it into ice at -10.0 C? The specific heat of ice is 2090 J/(kg K) and the latent heat of fusion of water is
210 kJ
A store sign, with a mass of 20.0 kg and 3.00 m long, has center of gravity at the center of the sign. It is supported by a loose bolt attached to the wall at one end and by a wire at the other end, as shown in figure above The wire makes an angle of 25.0 Degree with the horizontal. What is the tension in the wire?
232 N
How much heat is required to raise the temperature of a 225 g lead ball from 15.0 C to 25.0 C? The specific heat of lead is 128 J/(kgK).
288 J
How much heat is required to raise the temperature of a 225-g lead ball from 15.0 C to 25.0 C? The specific heat of lead is 128 J/(kgK)
288J
A 6.00 m length of rope has a mass of 700 g. It is pulled taught with a force of 100 N. What is the speed of waves on the rope?
29.3 m/s
A cylinder, semicircular in cross-section, 10.0 m long and 5.00 m in radius, is completely submerged in water. What is the buoyant force on the cylinder?
3.85x10^6
An ideal gas undergoes the process a->b->c->a-> shown in Figure above. Pa = Pc = 360.0 kPa, Vb = vc = 68.00 L, Va = 35.00 L, and Pb = 560.0 kPa. How much work is done by the system in this process?
3300J
A 35-g block of ice at -14 C is dropped into a calorimeter (of negligible heat capacity) containing 400 g of water at 0 C. When the system reaches equilibrium, how much ice is left in the calorimeter? The specific heat of fusion of water is 33.5x10^4 J/kg
38 g
A gas expands from an initial volume of 0.040 m^3 and an initial pressure of 210 kPa to a final volume of 0.065 m^3 while its temperature is kept constant. How much work is done by the system?
4.1 kJ
An object is moving in a circular path with an angular speed of 1.52 rad/s. How long does it take the object to complete one revolution?
4.13 s (divide 6.28[radians in one revolution] by 1.52)
A man is holding an 8.00 kg vacuum cleaner at arm's length, a distance of 0.550 m from his shoulder. What is the torque on the shoulder joint if the arm is horizontal?
43.2 Nm
Vector M = 4.00 m points eastward and vector N = 3.00 m points northward. The resultant vector M+N is given by
5.00 m at an angle 36.9 Degrees north of east
An incompressible fluid flows steadily through a pipe that has a change in diameter. The fluid speed at a location where the pipe diameter is 8.0 cm is 1.28 m/s. What is the fluid speed at a location where the diameter has narrowed to 4.0 cm?
5.12 m/s
An incompressible fluid flows steadily through a pipe that has a change in diameter. The fluid speed at a location where the pipe diameter. The fluid speed at a location where the pipe diameter 8.0 cm is 1.28 m/s. What is the fluid speed at a location where the diameter has a narrowed to 4.0 cm?
5.12 m/s
A simple pendulum of length 2.00 m is made with a mass of 2.00 kg. The mass has a speed of 3.00 m/s when the pendulum is 30.0 degrees above its lowest position. (A) What is the maximum angle away from the lowest position the pendulum will reach? (B) What is the speed of the mass when the pendulum is 45 Degrees above its lowest position?
50.5 Degrees, 1.66 m/s
A car starts out when the air temperature is 288 K. The air pressure int he tires is 500 kPa. After driving a while, the temperature of the air in the tires increases to 298 K. What is the pressure in the tires at that point assuming the volume remains constant?
517 kPa
The vertical displacement of a string is given by y(xt) = (6.00 mm)cos[(3.25 m^-1)x-(7.22^1)t] What is the amplitude of the wave?
6.00 mm
Two people are talking at a distance of 3.0 m from where you are and you measure the sound intensity as 1.1 x 10^-7 W/m^2. Another student is 4.0 m away from the talkers. What sound intensity does the other student measure?
6.2 x 10^-8 W/m^2
The peak of Mt. Everest, at 10,900 meters, is the highest point above sea level in the world. What is its elevation in miles?
6.77 miles
A truck is towing a car whose mass is one quarter that of the truck. The force exerted by the truck on the car is 6000 N. The force exerted by the car on the truck is
6000 N
The rms speed of a certain sample of carbon dioxide molecules, with a molecular weight of 44 g/mole is 396 m/s. What is the rms speed of water molecules, with a molecular weight of 18 g/mol at the same temperature?
619 m/s
A child is riding a merry-go-round, which has an instantaneous angular speed of 1.25 rad/s and an angular acceleration of 0.745 rad/s^2. The child is standing 4.65 m from the center of the merry-go-round. What angle does the acceleration of the child make the tangential direction?
64.5 Degrees
A 1200 kg car is pulling a 500 kg trailer along level ground. Friction is negligible. The car accelerates with an acceleration of 1.3 m/s^2. What is the force exerted by the car on the trailer?
650 N
A 200-kg superhero, falling from a building manages to grab hold of the end of a 3.0 m long flagpole, 5.0 cm in radius, which saves him from falling any further. After the oscillations have died down, the end of the flagpole is sagging 10 cm. What is the shear modulus of the pole?
7.5x10^6 N/m^2
A 600 kg car is going over a curve with a radius of 120 m that is banked at an angle of 25 degree with a speed of 30.0 m/s . The coefficient of static friction between the car and the road is 0.30. What is the normal force exerted by the road on the car?
7240 N
A 40.0kg crate is being raised by means of a rope. Its upward acceleration is 2.00 m/s^2. What is the force exerted by the rope on the crate?
80.0N
An object with a mass of 10.0 kg is at rest at the top of a frictionless inclined plane of height 8.00 m and an angle of inclination 30.0 degrees with the horizontal surface, as shown in Figure 8-9. The coefficient of kinetic friction of kinetic friction for the horizontal surface is 0.400 and g = 10.0 m/s^2. Refer to Figure above. What is the kinetic energy of the object at the bottom of the inclined plane?
800 J
A 10 kg sign is held by two ropes as shown in Figure above. What is the tension on rope A?
88 N
A person drops a brick from the top of a building. The height of the building is 400 m and the mass of the brick is 2.00 kg. What will be the speed of the brick right before it touches the ground? Use g = 10.0 m/s^2
89.4 m/s
You are on an airplane traveling with a constant velocity at an altitude of 20,000m. What is the acceleration of gravity at that altitude? The radius of Earth is 6.37 x 10^6 m.
9.81 m/s^2
If a vector A has components Ax<0, and Ay<0, then the angle that this vector makes with the positive x-axis must be in the range
90 degrees to 180 degrees
Above the velocity-versus-time graph for a basketball player traveling up and down the court in a straight line path. Find the displacement of the player for each of the segments A, B, C, and D.
A, 4m; B, 6m ; C, 8m; D, 0m
Four waves are described by the following expressions, where distances are measured in meters and times in seconds. I y = 0.12cos(3x-21t) II y = 0.15sin(6x+42t) III y = 0.13 cos(6x +21t) IV y = -0.23 sin(3x - 42t)
All of them have the same period
Consider three drinking glasses. All three have the same area base, and all three are filled to the same depth with water. Glass A is cylindrical. Glass B is wider at the top than at the bottom, and so holds more water than A. Glass C is narrower at the top than at the bottom, and so holds less water than A. Which glass has the greatest liquid pressure at the bottom?
All three have equal non-zero pressure at the bottom
Refer to the Figure above. The components of vectors A and B are
Ax = Acos90, Bx = -Bcos60, Ay = Acos90, By = Bcos30
Salt water has greater density than fresh water. A boat floats in both fresh water and in salt water. Where is the buoyant force greater on the boat?
Buoyant force is the same in both.
From the following statements regarding the ratio of the molar specific heat at constant pressure to the molar specific heat at constant volume, Cp/Cv, the only correct one for an ideal monatomic gas is
Cp/Cv > 1
A body moving with constant speed cannot be accelerating.
False
A component of a vector can be greater than the vector's magnitude.
False
A force is required for an object to move.
False
A wave pulse on a string whose end is fixed is reflected without inversion.
False
If work is done on a system by non-conservative forces, the total mechanical energy of a system stays constant.
False
Power is a vector quantity
False
Sound waves in air are transverse waves.
False
The acceleration of an object does not have to be in the same direction as the net force applied to it.
False
The buoyant force acting on an object is equal to the weight of the object.
False
The force of kinetic friction between two surfaces is dependent on the relative speed of the two surfaces.
False
The frictional force is a conservative force.
False
The preferred positive direction for angular displacement is the clockwise direction.
False
The work required to stretch a spring changes linearly with the amount of stretch.
False
Two objects are thrown vertically upwards simultaneously, one on the surface of Earth and the other on the surface of the Moon. Both have an initial velocity of 20 m/s. Both objects will take the same time to reach the highest point of their trajectory.
False
When a rigid body rotates about a fixed axis all the points in the body have the same angular displacement.
False
When a rigid body rotates about a fixed axis all the points in the body have the same tangential speed.
False
When objects stick together after colliding, the collision is completely elastic.
False
Work is a vector quantity
False
A dumbbell-shaped object is composed by two equal masses, m, connected by a rod of negligible mass and length r. If I1 is the moment of inertia of this object with respect to an axis passing through the center of the rod and perpendicular to it and I2 is the moment of inertia with respect to an axis passing through one of the masses we can say that
I1<I2
A sample of an ideal gas is slowly compressed to one-half its original volume with no change in temperature. What happens to the average speed of the molecules in the sample?
It does not change
When atmospheric pressure changes, what happens to the absolute pressure at the bottom of a pool?
It increases by the same amount
Two cars are traveling at the same speed and hit the brakes at the same time. One car has double the deceleration of the other. By what factor does the distance required to stop that car compare with that for the other car?
It takes half the distance to stop
A block of mass M slides down a frictionless plane inclined at an angle(theta) with the horizontal. The normal reaction force exerted by the plane on the block is
Mgcos(theta)
In the absence of an external force, a moving object will
Move with constant velocity
Two men, Joel and Jerry, push against a wall. Jerry stops after 10 min, while Joel is able to push for 5.0 min longer. Compare the work they do.
Neither of them do any work
A thermally isolated system is made up of a hot piece of aluminum and a cold piece of copper; the aluminum and the copper are in thermal contact. The specific heat capacity of aluminum is more than double that of copper. Which object experiences the greater magnitude gain or loss of heat during the time the system takes to reach thermal equilibrium?
Neither; both experience the same size gain or loss of heat
A wheel of radius R is rolling on a horizontal surface. Its center is moving forward with speed v. A point on the wheel a distance r/3 below the center is moving forward at a speed 2v/3. The wheel is
Rolling without slipping
A solid sphere, solid cylinder, and a hollow pipe all have equal masses and radii. If the three are released simultaneously at the top of an inclined plane, which will reach the bottom first?
Solid Sphere
The period of a pendulum is the time it takes the pendulum to swing back and forth once. If the only dimensional quantities that the period depends on are the acceleration of gravity, g, and the length of the pendulum, L, what combination of g and L must the period be proportional to? Acceleration has dimensions of [L][T^-2]
Square Root of (L/g)
On the Moon, the acceleration of gravity is g/6. If a pendulum has a period T on Earth, what will its period be on the Moon?
Square Root of 6/T
When you blow some air above a paper strip, the paper rises. This is because
The air above the paper moves faster and the pressure is lower
On a cold winter day you turn up the thermostat in your house. Assume that your house is well sealed and that no air enters or leaves the house. When the air temperature in your house rises a short while later, what statement is correct regarding the air pressure?
The air pressure is higher at the higher tempature
The rotating systems shown in Figure above differ only in that the two identical movable masses are positioned a distance r from the axis of rotation (left), or a distance r/2 from the axis of rotation (right). If you release the hanging blocks simultaneously from rest,
The block at the right lands first
In simple harmonic motion, the speed is greatest at that point in the cycle when
The magnitude of the acceleration is minimum
State Kepler's Third Law of Orbital Motion.
The period of a planet's orbit is proportional to the 3/2 power of its average distance from the Sun.
Two equal forces are applied to a door. The first force is applied at the midpoint of the door; the second force is applied at the doorknob. Both forces are applied perpendicular to the door. Which force exerts the greater torque?
The second at the doorknob
Sound intensity is defined as
The sound energy passing through a unit of area
A monatomic ideal gas is compressed isothermically to one-third of its initial volume. The resulting pressure will be
Three times as large as the initial value
When you walk barefoot in a room, the floor feels cooler walking on a tile floor as compared to a wooden floor because
Tile has a larger thermal conductivity than wood.
A net horizontal force is required for a body to move in a horizontal circle.
True
A particle that has zero momentum must also have zero kinetic energy.
True
All reversible engines operating between the same two temperatures have the same efficiency
True
An object floats on a fluid if its density is less than that of the fluid.
True
For uniform circular motion, the velocity and acceleration vectors are perpendicular to each other at every point in the path.
True
Heat is energy that is transferred between objects that are in thermal contact because of a temperature difference.
True
If a thermometer measures the temperature of two objects as being equal, you can conclude that if the objects are placed in thermal contact, no heat will flow between them.
True
In one-dimensional elastic collision of two identical masses, the masses exchange velocities.
True
Internal forces cannot change the total momentum of a system.
True
Non-conservative forces convert mechanical energy into other forms of energy, or convert other forms of energy into mechanical energy.
True
Order in one part of the universe can only be produced at the expense of disorder in another part.
True
The banking angle for a properly banked curve does not depend on the mass of the car going over it.
True
The center of mass of a continuous, uniform object is located at the geometric center of the object.
True
The center of mass of an object does not have to be located within the object.
True
The coefficient of static friction is always larger than the coefficient of kinetic friction.
True
The force acting on an object is said to be conservative if the work done by this force on the object is independent of the path chosen.
True
The force of kinetic friction between two surfaces is independent of the area of contact between the surfaces.
True
The gravitational force is a conservative force.
True
The horizontal component of the velocity of a projectile remains constant during the entire trajectory of the projectile.
True
The sum of kinetic and potential energies of an object is conserved only when the object is under the influence of conservative forces.
True
The vertical component of the acceleration of a projectile remains constant during the entire trajectory of the projectile.
True
When a rigid body rotates about a fixed axis all the points in the body have the same angular acceleration.
True
When comparing two gases at the same temperature, the molecules of the gas with the smaller molecular weight have the higher rms speed.
True
The highest tides occur when
When the Sun and the Moon are on the same side of the Earth.
Work done by static friction is always
Zero
Which of the following are characteristics of a mass in simple harmonic motion?
all of these
Consider a flat steel plate with a hole through its center as shown in Figure above. When that plate's temperature is increased, the hole will
always expand
For periodic motion, the maximum displacement from the equilibrium point is called the
amplitude
The wavelength corresponding to the harmonics of an organ pipe that is open at one end and closed at the other can be found by saying that the length of the pipe must be equal to
an odd number of quarter lengths
Curve A in Figure above represents
an underdamped situation
A mass attached to a vertical spring and bobs up and down between points A and B. Where is the mass located when its kinetic energy is a minimum?
at either A or B
Refer to Figure above. A bimetallic strip, consisting of metal G on the top and metal H on the bottom, is rigidly attached to a wall at the left. The coefficient of linear thermal expansion for metal G is greater than that of metal H. If the strip is uniformly heated, it will
curve downward
A liquid boils when it vapor pressure
equals the external pressure
In Figure above, the block of mass m is at rest on an inclined plane that makes an angle(theta) with the horizontal. The force of static friction f must be such that
f = mgsin(theta)
A boat loaded with rocks is floating in a swimming pool. If the rocks are thrown into the pool, the water level in the pool, after the rocks have settled to the bottom,
falls
An object is released from rest a height h above the ground. A second object with four times the mass of the first is released from the same height. The potential energy of the second object compared to the first is
four times as much
For a periodic process, the number of cycles per unit time is called the
frequency
What is the difference between the pressures inside and outside a tire called?
gauge pressure
A sound source departs from a stationary observer. The frequency heard by the observer is
lower than the source
The time for one cycle of a periodic process is called the
period
The process whereby heat flows in the absence of any medium is referred to as
radiation
The fact that a dew drop is spherical is best described in terms of
surface tension
The pitch of a sound is determined by
the frequency
Its more difficult to start moving a heavy carton from rest than it is to keep pushing it with constant velocity, because
uk < us
A block of mass m slides without friction on a table with speed v. It hits and compresses a spring of force constant k by a distance l. The spring then expands again ejecting the block in the opposite direction as it was originally traveling. Neglecting the mass of the spring, what is the speed of the object after it is ejected by the spring?
v
On a force vs. position graph, the area under curve is a representation of
work