Question

____ describes how fast something is going, whereas, __________ describes
how fast something is going in a certain direction. (1 point)

○ rate, velocity
○ speed, velocity
○ rate, speed
○ speed, acceleration

acceleration is any change in what two things? (select two) (1 point)

□ direction
□ speed
□ gravity
□ force

Explanation:

First Question (Multiple Choice)

To solve this, we recall the definitions:

• Speed is a scalar quantity that describes how fast an object is moving (magnitude only).
• Velocity is a vector quantity that describes both the speed and the direction of motion.
• Rate is a more general term (e.g., rate of change) and not specific to motion speed.
• Acceleration is the rate of change of velocity, not just speed with direction. So the correct pair is speed (describes how fast) and velocity (describes how fast in a direction).

Acceleration is defined as the rate of change of velocity. Velocity is a vector with magnitude (speed) and direction. So a change in speed (magnitude of velocity) or a change in direction (of velocity) both result in a change in velocity, hence acceleration. Gravity is a force, and force causes acceleration but is not what acceleration changes. Force is related to acceleration via \( F = ma \), but acceleration itself is about changes in velocity (speed or direction).

Answer:

B. speed, velocity

Second Question (Multiple Select)