Question

1. what is the difference between the velocity and the speed of an object?

a. velocity is the change in distance over time, while speed is the change in velocity over time.
b. velocity has no direction, while speed has a direction.
c. velocity is the change in speed over time, while speed is the change in distance over time.
d. velocity has a direction, while speed has no direction.

Explanation:

To solve this, we recall the definitions of velocity and speed. Speed is a scalar quantity (magnitude only, no direction) and is calculated as distance over time ($\text{speed}=\frac{\text{distance}}{\text{time}}$). Velocity is a vector quantity, meaning it has both magnitude and direction, and is calculated as displacement over time ($\text{velocity}=\frac{\text{displacement}}{\text{time}}$).

• Option A: Incorrect. Speed is distance over time, and acceleration is change in velocity over time. Velocity is displacement over time, not change in distance over time.
• Option B: Incorrect. Velocity has direction (vector), speed does not (scalar).
• Option C: Incorrect. Acceleration is change in velocity over time, speed is distance over time.
• Option D: Correct. Velocity (vector) has direction, speed (scalar) does not.

Answer:

D. Velocity has a direction, while speed has no direction.