 MCAS 2009 Session 2 Printer Friendly Version A man applies a force of 100 N to a rock for 60 seconds, but the rock does not move. What is the amount of work done by the man on the rock? The diagram below shows a ball moving in a circular path. Which of the following would cause the ball to fly off in a straight-line path? Four students of different weights timed themselves walking up a set of stairs. Their data are shown below. Which student used the most power while walking up the stairs? The graph below shows velocity measurements made as a car moved north for 25 s. How far did the car move during the first 15 s of the trip? The figure below represents a pendulum’s motion with the lowest point of its swing labeled P. What happens to most of the pendulum’s gravitational potential energy as it reaches the lowest point P? The diagram below shows a light ray striking a plane mirror surface at an angle of 40° to the normal. Which of the following diagrams shows the ray that is reflected from the plane mirror surface? In an electromagnetic wave, an electric field exists perpendicular to a magnetic field, and both fields are perpendicular to the direction of travel of the wave. These characteristics indicate that an electromagnetic wave is which of the following wave types? Large amounts of current can damage a circuit. Which of the following changes in a series circuit will result in an increase in current? Based on Ohm’s law, which of the following statements explains what must happen when the voltage across a resistor is decreased? A 1 kg block sliding to the right on a level, frictionless surface with a speed of 2 m/s collides and sticks to a second 1 kg block sliding to the left. After the collision, the blocks are motionless. What was the speed of the second 1 kg block before the collision? Which of the following is an example of a nonharmonic motion? A ball has a mass of 0.1 kg and an initial velocity of 20 m/s. The ball is given an acceleration of 30 m/s2 for 5 s. What is the net force on the ball during acceleration? Which of the following has the greatest momentum? The diagram below shows the path of a student on a sled starting from rest at point W. The student slides down a frictionless, snow‑covered hill past point Z, which is at ground level. Which of the following statements best describes the energy of the student and sled from point W to point Z? A circuit diagram is shown below. Which component in the diagram converts chemical energy into electrical energy? An electrostatic paint sprayer is used to spray paint evenly onto the surface of a car. Before the paint is sprayed, the car body is given a positive charge and the paint droplets are given a negative charge. The paint droplets experience an attractive force as soon as they are released from the sprayer. The paint droplets are originally sprayed at a distance of 30 cm from the car body, as shown below. Which of the following changes will cause the largest increase in the attractive force on the paint droplets? Which of the following is an example of an electromagnetic wave? Precise measuring instruments require shock absorbers to eliminate small vibrations that can affect the results of an experiment. One type of shock absorber that can be used is an electromagnet that repels a magnetic platform placed above it. Which of the following setups would provide the greatest lift to the platform? Which of the following statements best explains why it is usually easier to keep a sliding object moving than it is to start the object moving?

Open-Response Questions
• BE SURE TO ANSWER AND LABEL ALL PARTS OF THE QUESTION.
• If you do the work in your head, explain in writing how you did the work.

Refer to the following information for the next three questions. In a room at 21°C, 60 mL of water is poured into each of three cups. The water in cup 1 is at 15°C, the water in cup 2 is at 25°C, and the water in cup 3 is at 45°C.

 a. Describe what happens to the temperature of the water in each cup over a one-hour period.

 b. Describe what happens to the energy present in each cup over the one-hour period and explain why.

 c. Explain how equilibrium is reached in the cup.

Refer to the following information for the next four questions. Two athletes are lifting weights. Athlete X lifts 445 N a distance of 2 m in 4 s. Athlete Y lifts 445 N a distance of 2 m in 1 s. Assume that each athlete lifts the weights over his head the same distance from the floor.

 a.  Calculate the amount of work each athlete does. Show your calculations and include units in your answer.

 b.  Compare the amounts of work done by the two athletes. Explain your answer.

 d.  Compare the power used by athlete X with the power used by athlete Y. Explain your answer.

Refer to the following information for the next three questions. Rita and John stand at opposite ends of a long section of steel track from an abandoned railroad line. Rita places a penny on her end of the track. John then strikes his end of the track with a rock.

 a. Describe what Rita sees happen to the penny on the track and explain her observation. Rita puts her ear on the track. John strikes his end of the track with the rock again.

 b. Describe the difference in speed between the sound Rita hears in the air and the sound she hears through the track.

 c. With the rock, John strikes his end of the track harder than before. Identify which sound wave property he has changed. Related Documents