Force (Activity 1)

A mother and daughter press their hands together and push apart while ice skating.

Immediately after they push away from each other, how does the motion of the mother and daughter change?

• The mother moves forward, and the daughter moves backward with a greater acceleration.

• Both move forward, but the mother moves with a greater acceleration.

• The mother moves backward, and the daughter moves forward with a greater acceleration.

• Both move backward, but the daughter moves with a greater acceleration.

The net force on a vehicle that is accelerating at a rate of 1.5 m/s² is 1,800 newtons. What is the mass of the vehicle to the nearest kilogram?

The diagrams show forces acting on a toy car as it moves to the right. Which diagram shows the toy car that will most likely accelerate to the right based on these conditions?

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A 1,100 kg car comes uniformly to a stop. If the vehicle is accelerating at -1.2 m/s², which force is closest to the net forces acting on the vehicle?

• -9,600 N

• -1,300 N

• -900 N

• -94 N

A physics teacher performed a demonstration for a science class by pulling a crate across the floor and measuring the force with a spring scale. While she pulled, a student measured the acceleration of the crate with a handheld electronic device. The results of three trials are shown below.

The teacher asked the class to calculate the acceleration of the crate based on the crate's mass and the force she applied. What conclusion can be made about the difference between the calculated acceleration and the actual acceleration that occurred in the trials?

• Another force in the direction of the motion produced a lower acceleration than calculated.

• An opposing force caused by friction produced a lower acceleration than calculated.

• Another force in the direction of the motion produced a higher acceleration than calculated.

• An opposing force caused by friction produced a higher acceleration than calculated.

An archer shot a 0.06 kg arrow at a target. The arrow accelerated at 5,000 m/s² to reach a speed of 50.0 m/s as it left the bow.

During this acceleration, what was the net force on the arrow to the nearest newton?

A leaf fell from a tree branch. The path it followed is shown in the diagram below.

Which of these best describes why the leaf fell in a crooked path instead of straight down?

• Objects with irregular shapes never fall in straight lines.

• Air currents and gravity applied changing and unbalanced forces to the leaf.

• The upward force of the air on the leaf was greater than the downward force of gravity.

• Once the leaf was in motion, it continued moving in the same direction because the forces were balanced.

Two students are working together to build a birdhouse. Student 1 applies force of 10 N to a wooden board in order to slide it across the table to Student 2.

If the force of friction resisting the student's push is 4 N; what is the net force acting on the board?

• 4 N

• 6 N

• 10 N

• 14 N

Deep Space 1 was a spacecraft powered by an engine that gave off xenon particles to change velocity. It had a mass of 500 kg. Which expression can be used to find the spacecraft's acceleration if its engine created a net force of 0.10 N?

A golfer hits a golf ball with a club. The mass of the ball is 0.05 kg. The ball accelerates at 2,000 m/s².

What is the net force, the the nearest newton, that accelerates the ball?