Question

How do you find the average acceleration given a car travels from rest in a distance of 400m in 16 seconds?

Answer 1

Average acceleration is `25/8` `"m/sec"^2`

Explanation:

If an object starting from rest (uniform velocity `0`), at a uniform (or we may say average acceleration) acceleration `a`,
then final velocity after `t` time is `axxt` and distance covered is `1/2at^2`.

Here car travels from rest in a distance of `400m` in `16` seconds

Hence `400=1/2xxaxx16^2`

i.e. `a=(2xx400)/(16xx16)=(cancel2^1xxcancel400^25)/(cancel16^8xxcancel16^1)=25/8` `"m/sec"^2`