Question

Select three different examples of accelerated motion. a body traveling in a straight line and increasing in speed a body traveling in a straight line and decreasing in speed a body traveling in a straight line at constant speed a body standing still a body traveling at a constant speed and changing direction

Answer 1

This is the same question that I just answered.

Have present the definition of acceleration:

         a = Δv / Δt, this is change in velocity per unit of time.

a and v are in bold to mean that they are vectors.

1) a body traveling in a straight line and increasing in speed: CORRECT:

Acceleration is the change in velocity, either magnitude or direction or both. So, a body increasing in speed is accelerated.

2) a body traveling in a straight line and decreasing in speed: CORRECT

A decrease in speed is a change in velocity, so it means acceleration.

3) a body traveling in a straight line at constant speed: FALSE.

That body is not changing either direction or speed so its motion is not accelerated but uniform.

4) a body standing still : FALSE.

That body is not changind either direction or speed.

5) a body traveling at a constant speed and changing direction: CORRECT.

The change in direction means that the body is accelerated. The acceleration due to change in direction is named centripetal acceleration.