# When is acceleration not constant?

##### 2 Answers

Mar 22, 2018

#### Answer:

Acceleration is not constant whenever there's a change in velocity

#### Explanation:

Acceleration is defined as

Whenever there is a change in velocity, either due to a change in speed or a change in direction, there will be non-zero acceleration.

Mar 22, 2018

#### Answer:

Acceleration is not constant if the net force is not constant.

#### Explanation:

Imagine a rocket propelled car. It has 3 rockets on the back. All the rockets ignite and forward acceleration is constant at 3g's. Then one of the engines has a malfunction and quits. The acceleration changes to 2 g's. The acceleration was not constant because the force was not constant.

I hope this help,

Steve

P.S. In cases where acceleration is constant at some non-zero value, velocity will be changing.