OSM Force, Motion and Energy 4 SOL Review

Four boxes are sliding with constant speed before each box experiences an unbalanced force of 8 N. Which box would experience the greatest acceleration when the unbalanced force is applied?

• The box with a mass of 2 kg

• The box with a mass of 4 kg

• The box with a mass of 6 kg

• The box with a mass of 8 kg

The unusual strength of a glue makes it able to hold a heavy object, or load, as shown in the diagram below. If the load exerts a strong downward force, the glue —

• destroys the force

• exerts a stronger downward force

• causes the load to accelerate upward

• exerts an upward force that is equal to the downward force

Two forces are applied to a 17 kg box, as shown. The box is on a smooth surface. Which statement best describes the acceleration of the box?

• The box accelerates at 1.0 m/s² to the right because the net force is 17 N to the right.

• The box accelerates at 1.9 m/s² to the right because the greater force is to the right.

• The box accelerates at 3.0 m/s² because the combined forces cause the box to accelerate.

• The box does not accelerate, because neither force is large enough to move the box.

Which objects in the list experience an unbalanced force?

• The book, the ball, and the car

• The ball, the car, and the bird

• The can, the swing, and the bird

• The book, the ball, the can, and the swing

During which procedures did students observe an unbalanced upward force on Box 1?

• Procedures 1, 2, and 3

• Procedures 4 and 5

• Procedures 3 and 4

• Procedures 1, 3, and 5

NASA’s space shuttle program was active from 1981 until 2011. The photograph shows rockets carrying a space shuttle off the launchpad. How can Newton’s law of action-reaction best be applied to explain the movement of a rocket?

• As the fuel burns, gases push against the rocket, moving it upward.

• As the fuel burns, gases move out of the rocket and reduce air resistance.

• As the fuel burns, the mass of the rocket decreases.

• As the fuel burns, the rocket moves faster.

During a demonstration of Newton’s laws of motion, a student used the setup shown in Figure 1. The student flicked the index card with a fingertip, and the coin fell straight down into a plastic cup as shown in Figure 2. Which of these best explains why the coin fell straight down into the cup instead of remaining on the index card?

• F. The coin was at rest until the card was removed, so it tended to remain in the same location. Once the card was gone, the unbalanced force of gravity caused the coin to fall.

• G. Moving the card applied an action force on the coin. Since the card was gone, gravity applied a reaction force on the coin.

• H. The card had less mass than the coin, so a smaller force of gravity acted on the card. The larger force of gravity on the coin made it fall.

• J. The acceleration of the coin falling into the cup was equal and opposite to the acceleration of the card.

The diagram below shows two different forces acting on a cyclist riding a bicycle. The total mass of the cyclist and the bicycle is 100.0 kg. Based on this information, what is the acceleration of the cyclist?

• 0.66 m/s² backward, because the force of the air slows the cyclist down

• 0.66 m/s² forward, because the applied force is greater than the force of the air

• 2.3 m/s² backward, because the forces are opposite and not equal

• 2.3 m/s² forward, because the cyclist’s inertia is greater than the force of the air

A student jumps off a sled toward the west after it stops at the bottom of an icy hill. Based on the law of action-reaction, in what direction will the sled most likely move as the student jumps off?

• North

• South

• East

• West

• A) Different surfaces affect how fast a toy car accelerates.

• B) Different toy cars travel at different speeds.

• C) Gravity has little effect on the speed of toy cars on different surfaces.

• D) Air resistance is the greatest factor in limiting the acceleration of different toy cars.