Describing Motion

A student is a passenger in the front seat of a moving car. Which object below is the best frame of reference for the student to determine how fast the car is moving relative to the ground?

• The driver sitting next to the student.

• A truck traveling in the lane next to the car.

• An airplane flying overhead.

• A signpost on the side of the road.

A place or object used for comparison to determine if something is in motion is called

• acceleration.

• reference point.

• speed.

• velocity.

Imagine you are flying in an airplane, cruising over the ocean at a fixed altitude. If you choose the ocean far beneath your window as a fixed reference point, the airplane and everything inside it will appear to be

• stationary.

• in motion.

To calculate velocity, you need to know the total

• distance of the motion.

• time of the motion.

• distance and time of the motion.

• distance, time, and direction of the motion.

Velocity is

• the same as speed.

• speed in a given direction.

• the same as acceleration.

• negative acceleration.

Two objects traveling at the same speed have different velocities if they

• start at different times.

• travel different distances.

• move in different directions.

• have different masses.

A car traveled 200 miles in 4 hours. Calculate the car's speed of motion.

• 50

• 50 miles

• 50 hours

• 50 miles per hour

The delivery route for a mail truck is pictured below. Each square represents a city block, and the path of the truck is represented by arrows. The truck began and ended at the same location. What was the displacement of the mail truck?

• 0 blocks.

• 6 blocks

• 12 blocks

• 16 blocks

What is the displacement from the student's home to her school?

• 3 km

• 3 km NE

• 5 km

• 5 km NE

A plane travels 600 mph for the first three hours of the trip. Then, the plane travels at a constant speed of 300 mph for two hours. Calculate the plane's average speed.

• 480 mph

• 100 mph

• 180 mph

• 50 mph