8th Grade Midterm Physical Science

Which statement best describes Frame of Reference

• a. Motion is relative to position of the observer.

• b. Motion is relative to your personal opinion.

• c. Motion cannot be described without using a graph.

• d. Wait, have we been studying motion this entire time??

M1.1 Two observers (standing on different sides of the road) make observations about a car driving by. The observations are different. Which could explain the difference in their observations of the motion of the car?

• a. One of them must be wrong.

• b. Both of them must be wrong.

• c. They can both be correct, but simply viewing from different frames of reference.

• d. It’s impossible to make observations of the car.

M2.1 What is the total distance traveled from time t = 0 s to time t = 20 s?

• a. 26 cm

• b. 24 cm

• c. 4 cm

• d. 12 cm

M2.1 What is the total displacement from time t=0 s to time t=20 s?

• a. +26 cm

• b. + 24 cm

• c. +4 cm

• d. +12 cm

M2.2 What is the average velocity of the trip from time t=0 s to time t=20 s?

• a. +1.3 cm/s

• b. +1.2 cm/s

• c. +0.2 cm/s

• d. +0.6 cm/s

M2.2 In order to compute the average speed of a trip, you would find the total _ (time, distance or displacement) and divide by the total _ (time, distance, or displacement).

• time, distance

• distance, time

• time, displacement

• displacement, time

M2.2 An object starts in one position, travels in a large circle and ends at the same position. What is the best description of the average velocity of the entire trip?

• a. The average velocity was greater than the average speed.

• b. The average velocity was less than the average speed.

• c. The average velocity was the same as the average speed.

• d. You cannot determine the average velocity or the average speed.

M2.2 Which object has the greatest velocity?

• a. object A

• b. object B

• c. They are traveling at the same velocity.

• d. Not enough information to tell.

M2.2 When the two lines intersect at 3 seconds,

• a. they are traveling at the same velocity.

• b. they are at the same position.

• c. they are changing direction.

• d. they have covered the same distance.

M2.3 Which of the following would describe the acceleration for the object shown in the velocity vs. time graph from 15-30 minutes?

• a. Zero acceleration.

• b. Negative acceleration.

• c. Positive acceleration.

• d. We do not have enough information to describe the acceleration.