Question

2. A car traveling at 80 m/s speeds up to 90 m/s in 2 seconds. What is the acceleration of the car?

Answer 1

`\boxed {\boxed {\sf a= 5 \ m/s^2}}`

Step-by-step explanation:

We want to calculate the acceleration of the car. Acceleration is the change in velocity over the change in time.

`a= ( \Delta v)/(\Delta t)`

The change in velocity is the difference between the final velocity and the initial velocity.

`a= (v_f-v_i)/(\Delta t)`

The car speeds up from 80 meters per second to 90 meters per second. Therefore,

• 
  `v_f`= 90 m/d
• 
  `v_i`= 80 m/s
• 
  `\Delta t`= 2 s

Substitute these values into the formula.

`a= \frac {90 \ m/s - 80 \ m/s}{2 \ s}`

Solve the numerator and subtract.

`a= (10 \ m/s)/(2 \ s)`

Divide.

`a= 5 \ m/s/s`

`a= 5 \ m/s^2`

The acceleration of the car is 5 meters per second squared.