Sonar is a technology that uses sound waves to measure distances underwater. Sonar can be used by a ship to produce a detailed image of the bottom of an ocean. The diagram shows a ship using sonar.

 

What must happen to a sound wave emitted by the ship to produce the detailed image?

 In an investigation, a strong magnet is passed through a coil of wire that is connected to a light bulb, as shown in the diagram.

 

 

What does this investigation best demonstrate?

 A net force is acting on an object. Which of the following graphs shows the object’s position over time?

Two toy cars, car R and car S, moved toward each other at a constant speed. Car R had a mass of 2 kg, and car S had a mass of 3 kg, as shown.

 

 

Part A: What was the total momentum of the system as the cars moved toward each other?

Part B: The incomplete table shows the velocity of each car at different times. At 2.5 s, the cars collided and bounced off each other. Assume no energy was lost to the environment.

 

 

What was the velocity of car R at 2 s?

The graph shows the velocity of an object over time, with intervals labeled U–Z.

 

 

During which two intervals is the direction of the net force acting on the object opposite to the direction of the object’s motion?

 

A student builds a circuit with a battery and a resistor, as shown in diagram 1. The student then adds another resistor to the circuit, as shown in diagram 2.

 

 

Which of the following describes how the current in the circuit changes when the student adds the second resistor?

Cats play and sleep on cat towers. A cat tower with two platforms is shown. One platform is 1.8 m above the ground, and the second platform is 1.1 m above the ground.

 

 

Part A: A 1.5 kg cat sat on the 1.8 m platform. What was the gravitational potential energy of the cat relative to the ground?

Part B: The cat jumped from the 1.8 m platform to the 1.1 m platform. Which of the following best describes the gravitational potential energy (GPE) and the kinetic energy (KE) of the cat as it was moving to the 1.1 m platform?

A railroad car with a mass of 400,000 kg is moving at a speed of 8.0 m/s toward a stationary railroad car with a mass of 1,200,000 kg, as shown in the diagram.

 

 

The moving car connects to the stationary car. Both cars then move in the same direction the first car was moving. What is the speed of both railroad cars after they connect?

Two 65 kg performers are using a teeterboard to perform a routine. One of the performers is at rest on the right side of the teeterboard while the other performer steps off a 3.0 m platform and lands on the left side of the teeterboard. The teeterboard and performers are shown.

 

        

 

After the performer on the left comes to rest on the left side of the teeterboard, the performer on the right moves upward and reaches a maximum height of 2.1 m, as shown above.

 

What is the percent efficiency of the teeterboard for this routine?

A circuit with two resistors is shown.

 

 

The voltage drop across the 10 Ω resistor is

Questions #35 through #38 focus on the motion of athletes. Read the information below and use it to answer the three selected response questions and one constructed-response question that follow.

 

Track and field is a sport that consists of many different events, including the 100 m sprint and the high jump.

 

100 m Sprint - Athlete K

 

The 100 m sprint is a short running race. Athlete K completed a 100 m sprint in 10.9 s. The table shows athlete K’s average velocity for each 10 m segment of the running race.

 

 

High Jump - Athlete M

 

The high jump is an event in which an athlete runs toward a bar and then jumps over it. Athlete M completed a high jump and then safely collided with a foam pad. Athlete M’s mass was 80 kg. The diagram shows several positions of athlete M during the high jump, with four positions labeled W, X, Y, and Z.

 

 

 

Which of the following shows athlete M’s high jump positions X, Y, and Z from least to greatest gravitational potential energy (GPE)?

Open Response #38 is located at the bottom of the page.

 

A car safety engineer is conducting an investigation to analyze the performance of three types of airbags. The engineer installs a different type of airbag in each of three identical cars. Each car will be crashed into a wall. At the time of the collision, sensors inside the cars will measure the collision forces applied by each airbag. The airbag that applies the lowest forces on its car’s sensors will be considered the most successful.

 

Which of the following should be controlled in the investigation?

A sled with a mass of 5 kg begins at rest on top of a hill at position Q. The sled moves down the hill and comes to rest on top of the next hill at position R, as shown.

 

 

As the sled moves from position Q to position R, how does the mechanical energy of the sled change?

This open response question has three parts (A, B, and C). It is a continuation of the information given in Questions ##35 through #37.

 

Another athlete, athlete L, completed a 100 m sprint in 9.6 s. The graph shows athlete L’s velocity over time. Four time intervals are labeled P, Q, R, and S.

 

 

A. Identify the interval of the race when athlete L had the greatest acceleration. Explain your reasoning.

C. The objects are released and start to move.

 

Identify whether the magnitude of the electrostatic force acting on object Z increases, decreases, or remains the same after the objects are released. Explain your reasoning.