Question

A car advertisement claims that a certain car can accelerate from rest to 70 km/hr in 7 seconds find the car acceleration

Answer 1

acceleration
`\approx 2.78\,\,(m)/(s^2)`

Explanation:

The acceleration is the change in velocity per unit of time.

Therefore to have this rate in appropriate units that can combine, we re-write the change from 0 to 70 km/h in meters per second using:

`70 (km)/(h) = (70000)/(3600) (m)/(s)`

so in this case the acceleration becomes:

`accel=(change\,\,vel)/(change\,\,time) =(70000m)/(3600\,*7\,s^2) \approx 2.78\,\,(m)/(s^2)`