Question

When a car moves uniformly from 42 km/h to68km/h in 30s. find distance travelled by the car?

Answer 1

The car traveled a distance of `216.66m~=2xx10^2m`.

Explanation:

`[(68km)/h]xx[(1000m)/(km)]xx[(1h)/(3600s)]~=18.889m/s`

`[(42km)/h]xx[(1000m)/(km)]xx[(1h)/(3600s)]~=11.667m/s`

Since the velocity increases at a constant rate, that is the acceleration is constant, we can use this simple velocity formula.

`Deltav=(Deltad)/(Deltat)`
where v is velocity, d is distance, and t is time. The delta symbol,

`Delta`, simply means the change or difference in values.

Rearrange this velocity formula to find distance, d.

`Deltad=(Deltav)xx(Deltat)`

Now substitute the values in for their respective variables.

`Deltad~=(18.889m/s-11.667m/s)xx30s~=(7.222)xx30s~=216.66m~=2xx10^2m`