Physics Review

Which of the following best describes the velocity of an object?

• 30 m/s

• 30 m east

• 30 m/s east

• $30\ \left(\frac{m}{s}\right)^2$
  

Four boxes are sliding with constant speed before each box experiences an unbalanced force of 8N. 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 6 kg

• The box with a mass of 8 kg

What is the difference between the velocity and the speed of an object?

• Velocity has a direction and speed has no specific direction

• Velocity does not have a direction and speed has a direction

A large rock is motionless on a flat sidewalk. Which statement best explains why the rock remains motionless?

• There are no forces acting on the rock

• The only force acting on the rock is directed toward the sidewalk

• The forces acting on the rock are all balanced.

Which objects all experience an unbalanced force?

• book, ball, and car

• ball, car, bird

• can, swing, bird

What is the difference between kinetic and potential energy?

• kinetic: stored energy, potential: energy in motion

• kinetic: energy in motion, potential: stored energy

A meteor is moving 468 km/min traveling in a south-to-north direction passed near Earth in 2013. Because the meteor was only 45 m wide, and was 27,700 km above Earth's surface. Which statement describes the meteor's motion?

• its velocity was 7.8 km/s northward

• its speed was 468 m/s northward

• its distance was 468 m

An 1,100 kg car is coming to a stop. If the vehicle is accelerating at -1.2 m/s^2, which force is closest to the net force?

• -9,600 N

• -1,300 N

• -900 N

Energy transformation in a battery

• chemical to mechanical

• chemical to electrical

• electrical to chemical

Energy transformation in vibrating speakers

• chemical to mechanical

• mechanical to sound

• sound to mechanical