#### Question

A car acquire a velocity of 72 km per hour in 10 second starting from rest. Find

(1) the acceleration,

(2) the average velocity, and

(3) the distance travelled in this time.

#### Solution

We have the following information,

Initial velocity, (u) = 0 m/s

Final velocity

`(v)` = 72 km/hr

= `"72(1000)"/3600` m/s

= 20 m/s

Time taken , (t) = (10) s

(i) So acceleration,

`a = (v-u)/t`

Put the values in the above equation to get the value of acceleration

`a = (20-0)/10`

= 2 `"m/s"^2`

(ii) we have to find the average velocity. we will use the following relation,

Average velocity = `"Initial velocity + Final velocity"/2`

So , Average velocity = `(v+u)/2`

Therefore putting the value in the above to get the avearge velocity ,

Average velocity = `(20+0)/2` m/s

= 10 m/s

(iii) We have to calculate the distance travelled. We will use the relation,

Distance travelled = (Average velocity) (Time)

So distance travelled is,

= (10)(10) m

= 100 m