Rock XX is released from rest at the top of a cliff that is on Earth. A short time later, Rock YY is released from rest from the same location as Rock XX. Both rocks fall for several seconds before landing on the ground directly below the cliff. Frictional forces are considered to be negligible.

Which of the following graphs best represents the vertical displacement of Rock XX as a function of time starting from immediately after the rock is released from rest? Take the positive direction to be downward.

Rock XX is released from rest at the top of a cliff that is on Earth. A short time later, Rock YY is released from rest from the same location as Rock XX. Both rocks fall for several seconds before landing on the ground directly below the cliff. Frictional forces are considered to be negligible.

After Rock YY is released from rest several seconds after Rock XX is released from rest, what happens to the separation distance SS between the rocks as they fall but before they reach the ground, and why? Take the positive direction to be downward.

An object travels along a straight, horizontal surface with an initial speed of 2 ms2 ms. The velocity of the object as a function of time is given in the table above. Which of the following graphs represents the object’s acceleration as a function of time?

Two objects, object X and object Y, are held together by a light string and are released from rest near a planet’s surface in the orientation that is shown in the figure. Object X has a greater mass than object Y. A graph of the acceleration as a function of time for the system’s center of mass is shown for the 4s. The positive direction is considered to be upward. How does the speed of object X vx compare to that of the system’s speed vs after the objects have fallen for 4s?

A student uses a motion sensor to collect data of the velocity of an object as a function of time during two experimental trials, as shown. In which trial does the object have the greatest magnitude of acceleration(GMA), and in which trial does the object travel the greatest distance(D)?

Car XX and car YY travel on a horizontal surface along different parallel, straight paths. Each car’s velocity as a function of time is shown in the graph. Which of the following claims is correct about car XX and car YY?

An object is launched upward at angle θ above the horizontal with a speed of v0. The trajectory and three positions of the object, XX, YY, and ZZ, are shown in the figure. Position XX is higher than position ZZ with respect to the ground, and position YY is at the object’s maximum vertical position. Which of the following claims is correct about the system that consists of only the object?

The table shows the vertical position as a function of time for an object that is dropped from a height of 5 m5 m. A student must determine the acceleration of the object. Which of the following procedures could the student use to make the determination? Justify your selections. Select two answers.

An object is held at an unknown height above Earth’s surface, where the acceleration due to gravity of the object is considered to be constant. After the object is released from rest, a student must determine the object’s speed the instant the object makes contact with the ground. Which of the following equations could the student use to determine the object’s speed by using the fewest measuring tools if the student does not have access to a motion sensor? Select two answers.

A toy car has a battery-powered fan attached to it such that the fan creates a constant force that is exerted on the car so that it is propelled in the opposite direction in which the fan blows air. The car has a carriage that allows a student to attach objects of different masses, as shown above. The fan has only one speed setting. All frictional forces are considered to be negligible. Which of the following procedures could be used to determine how the mass of the fan-car-object system affects the acceleration of the system?

Block AA is placed on a rough surface inclined at an angle θθ above the horizontal. A taut string connects block AA over a pulley to block BB, which hangs from the string, as shown below. The masses of blocks AA and BB are MAMA and MBMB, respectively. At time t=0t=0, block AA is sliding up the slope as block BB falls, and the blocks are both slowing down. Assume that the mass and friction of the pulley are negligible.The two blocks eventually stop and reverse direction. Which of the following graphs best predicts the acceleration of block AA as it moves up and down the rough, inclined surface? Assume that the positive direction points down the slope.

A student pulls a block over a rough surface with a constant force FPFP that is at an angle θθ above the horizontal, as shown above. If FPFP remains constant but the angle θθ is increased, which of the following is true at some later time?

An object is at rest on the ground. The object experiences a downward gravitational force from Earth. Which of the following predictions is correct about why the object does not accelerate downward? Select two answers. Justify your selections.

A scientist designs an experiment that requires two atomic particles whose only fundamental force exerted between them is the gravitational force. Which combination of particles and separation distance will meet this condition?

Planet X has a mass of MM and a radius of RR. Planet Y has a mass of 3M3M and a radius of 3R3R. Identical satellites orbit both planets at a distance RR above their surfaces, as shown above. The planets are separated by such a large distance that the gravitational forces between them are negligible.

How does the gravitational field gXgX at the surface of Planet X compare with the gravitational field gYgY at the surface of Planet Y?

A moon orbits a planet in a nearly circular orbit of radius RR, as shown in the figure.

The moon has a mass of 1×1022 kg1×1022 kg, and the gravitational field strength at a distance RR from the planet is 0.001 N/kg0.001 N/kg. What is the gravitational force exerted on the moon while it is in orbit around the planet?

Satellite AA orbits a planet at a distance dd from the planet’s center with a centripetal acceleration a0a0. A second identical satellite BB orbits the same planet at a distance 2d2d from the planet’s center with centripetal acceleration abab. What is the centripetal acceleration abab in terms of a0a0 ?

An object is placed on a rotating disk. The amount of time it takes the object to make one revolution around the center of the circle may be set at a known value. Which of the following procedures could be used to make the necessary measurements to find the coefficient of static friction between the object and the disk’s surface?

A rocket on Earth experiences an upward applied force from its thrusters. As a result of this force, the rocket accelerates upward at 2  m/s22  m/s2. Assume that there are no other upward forces exerted on the rocket and that wind resistance is negligible. Which of the following combinations of the rocket’s mass mRocketmRocket and force from its thrusters FThrustersFThrusters would result in an upward acceleration of 2  m/s22  m/s2? Select two answers.

A 2 kg object is released from rest near the surface of a planet with a negligible atmosphere. A graph of the object’s speed vv as a function of time tt is shown. What is the weight of the object on the planet?

A student uses a motion sensor to collect data about an object’s velocity vv as a function of time tt after it is released from rest near Earth’s surface. The student claims that the graph shown represents the object while in free fall. Does the data from the graph support the student’s claim?

Student XX ties one end of a string to a 0.50.5 kgkg ball and swings the ball in a vertical circle of radius 1 m1 ⁢m, as shown in the figure. Student YY uses video analysis to determine the speed of the ball at points AA, BB, CC, and DD, as shown in the table. Student XX states that the data are incorrect because the tension in the string provides a centripetal force that should cause the ball to travel with a constant tangential speed. Is Student XX’s reasoning correct, and why or why not?

A student swings a ball of mass MM on the end of a string in a vertical circle of radius R, as shown in the top figure above. Also shown is a diagram representing all of the forces exerted on the ball at the bottom of the circle, where its speed is v0v0. What is the magnitude of the acceleration of the ball at the bottom of the circle?

A car travels with a tangential speed v1v1 around a curve of radius rr and turns to the left, as shown by the rear view of the car in Figure 1. A force diagram of the forces exerted on the car with speed of 5m as it turns is shown in Figure 2. A force diagram of the forces exerted on the car with speed vv as it turns around the same curve of the same radius is shown in Figure 3. The speed vv of the car in figure 3 is most nearly

A student places a block on a disk, and the edge of the disk makes one revolution in a constant time interval △t▵t. A force probe is attached to the block and the center of the disk, as shown above. In an experiment, a student measures the centripetal force exerted on the block when placed at various distances from the center of the disc while the tangential speed of the edge of the disc remains constant. Which of the following graphs shows the centripetal force exerted on the block as a function of its distance from the center of the disk?

One end of a string is attached to a ball, with the other end held by a student such that the ball is swung in a horizontal circular path of radius RR at a constant tangential speed. At a later time, the tension force exerted on the ball remains constant, but the length of the string is decreased to R/4. What is the new tangential speed of the ball?

A student must test the maximum force exerted on an object attached to a string before the string breaks. The student ties the object of mass m0m0 to one end of the string and then uses the other end of the string to spin the object at a constant speed so that the object travels in a horizontal circular path, as seen in Figure 1. Figure 2 shows the horizontal force exerted on the object at time t0t0. In a second trial, what should the student do to increase the tension in the string while keeping all other quantities constant? Select two answers.

Two satellites orbit a planet of mass MM, as shown above. Satellite AA of mass 2 m2 m travels in a circular orbit of radius RR. Satellite BB of mass mm travels in a circular orbit of radius 2 R2 R. Each satellite travels at a constant tangential speed. How does the gravitational force, FgAFgA, exerted on satellite AA from the planet compare with the gravitational force, FgBFgB, exerted on satellite BB from the planet?

An object starts at rest and moves in a horizontal circle such that its tangential speed increases linearly as a function of time. Which of the following graphs shows how the centripetal acceleration behaves as a function of time?

The total mechanical energy of a system as a function of time is shown in the graph. Which of the following statements is true regarding the system?

A block on a rough, horizontal surface is attached to a horizontal spring of negligible mass. The other end of the spring is attached to a wall. The spring is compressed such that the block is located at position XX. When the block-spring system is released, the block travels to the right through position YY and continues to travel to the right through position ZZ. Free body diagrams for the block at positions XX, YY, and ZZ are shown in the figure. At which position does the block have the greatest kinetic energy?

A ball of mass MM is attached to a string of negligible mass that has a length RR. The ball moves clockwise in a vertical circle, as shown above. Which of the following is true about the ball-string-Earth system as the ball moves from point 11 to point 22?

A small block of mass M=0.10 kgM=0.10 kg is released from rest at point 1 at a height H=1.8 mH=1.8 m above the bottom of a track, as shown in the diagram. It slides down the track and around the inside of a loop of radius R=0.6 mR=0.6 m. The speed of the block is 2.5 m/s2.5 m/s at point 3. Which of the following claims about the situation is correc

One end of a vertical spring is attached to the ground with the other end above the ground such that the spring is at its equilibrium position. The spring has negligible mass and a spring constant k0k0 , as shown in Figure 1. When an object of mass m0m0 is released from rest above the spring, the object falls and then makes contact with the top of the spring with a speed v0v0 , as shown in Figure 2. The spring then compresses such that the object reaches a position x0x0 below the spring’s equilibrium position, as shown in Figure 3, where the object comes to rest. The object is then directed upward by the spring until it is no longer in contact with the spring. The object then continues upward. The object-spring-Earth system has zero gravitational potential energy at the instant shown in Figure 2. All frictional forces are considered to be negligible.

When the object is located at the position shown in Figure 3, which of the following equations correctly indicates the total mechanical energy of the object-spring-Earth system?

A student performs an experiment in which an applied force is exerted on a 4kg4kg object that is initially at rest. In the experiment, the applied force is exerted on the object until the object has moved a known distance. In all the experiments the applied force is exerted in the direction of motion. A motion detector measures the speed of the object after it has traveled the distance under consideration for a given trial. The table contains the data that were collected for three trials of the experiment. Which of the following conclusions can be drawn from the data? Select two answers.

A block of mass MM is placed on a semicircular track and released from rest at point PP, which is at vertical height H1H1 above the track’s lowest point. The surfaces of the track and block are considered to be rough such that a coefficient of friction exists between the track and the block. The block slides to a vertical height H2H2 on the other side of the track. How does H2H2 compare to H1H1?

An experiment is conducted such that an applied force is exerted on an object as it travels across a horizontal surface with a constant speed. A graph of the applied force exerted on the object as a function of the object’s distance traveled is shown. Which of the following claims is correct regarding the work done on the object by the applied force from one data point to the next data point?

Go over Unit 4 MCQ Part B