Question

What is the acceleration of an object that goes from 45m/s to 10 m/s in 5 seconds?

Answer 1

`\boxed {\boxed {\sf a= -7 \ m/s^2}}`

Step-by-step explanation:

Acceleration is the change in velocity over time.

`a= \frac {v_f-v_i}{t}`

The object accelerates from 45 meters per second to 10 meters per second in 5 seconds. Therefore,

`v_f=10 \ m/s \\v_i= 45 \ m/s \\t= 5 \ s`

Substitute the values into the formula.

`a= ( 10 \ m/s - 45 \ m/s)/(5 \ s)`

Solve the numerator.

`a= \frac { -35 \ m/s}{5 \ s}`

Divide.

`a= -7 \ m/s/s`

`a= -7 \ m/s^2`

The acceleration of the object is -7 meters per square second. The acceleration is negative because the object's velocity decreases and the object slows down.