Reviewer

Based on the text above, your fourth question.

The tortoise moved slowly and steadily. The hare ran quickly, then fell asleep near the finish line. Identify the following quantities as scalar or vector, respectively: the average velocity of the tortoise during the entire race, the acceleration of the hare during the first 2 minutes of the race and the time it takes for the tortoise and the hare to finish the race.

• vector, vector, scalar
• scalar, scalar, vector
• vector, scalar, vector
• scalar, vector, scalar

If the acceleration of an object is in the opposite direction as the velocity, which of the following happens?

• the object speeds up
• the object slows down
• the object remains at rest
• nothing happens to the object

Suppose an object moving forward changes its velocity from 15 m/s to 6m/s. What is the change in velocity?

• -21m/s
• -9m/s
• 9 m/s
• 21 m/s

Acceleration is represented by the slope of a

• velocity-time graph
• position-time graph
• distance-time graph
• acceleration-time graph

A meteor goes from +1.0 km/s to 2.2. km/s in 0.04s. What is its acceleration?

• 0.03 km/s2
• 30 km/s2
• 55 km/s2
• 80 km/s2

Which of the following units is associated with?

• s
• m
• km
• m/s

Which of the following describes a scalar quantity?

• it has direction only
• it has magnitude only
• it is the size of a quantity
• it has both direction and magnitude

Use the following motion diagram representing a ball moving across a horizontal table to answer the question. Which of the following statements are descriptions of the motion of the ball? I - The ball is in uniform motion. II - The ball is moving from left to right. III - The displacement between t1 and t2 is the same as the displacement between t2 and t4.

• I and II only
• I and III only
• II and III only
• I, II, and III

The average velocity of a plane was 600 km/h [N]. How long did it take the plane to travel 120km?

• 0.2 min
• 5 min
• 12 min
• 5.0 h