Question

A body starts from rest and accelerate uniformly at 5ms–2. Calculate the time taken by the body to cover a distance of 1km

Answer 1

We will use one of the laws of motion to solve this question i.e. this numerical which is as follows:

$\bold{S=ut+\frac{1}{2} at^2}$

We have the following information:

S ( distance to be covered in a straight line or distance covered in a straight line ) = 1 km = 1000 m

a ( acceleration ) = $\bold{5 m/s^2}$

u ( initial velocity ) = 0 m/s

Let us substitute the values now :)

$\bold{1000 = ( 0 \times t ) + \frac{1}{2} \times 5 \times t^2}$

Let us begin simplifying now!

$\bold{1000 = 0 + \frac{5}{2} \times t^2}\\ \\ \bold{\frac{1000 \times 2}{5} = t^2}\\ \\\bold{t^2 = 200 \times 2}\\ \\ \bold{t^2 = 400}\\ \\ \bold{t = \sqrt{400}} \\ \\ \bold{t = 20 ~seconds}$

Hence,

The body will take 20 seconds to cover a distance of 1000 m i.e. 1 km.

Answer 2

Here is your solution

Given :-

accelerate uniformly at 5ms^2.(V)

initial velocity = 0m/s (u)

Distance = 1km = 1000m

To find time :-

we know that

s   = ut + 1/2at^2

1000 = 0×t + 1/2×5×t^2

1000 = 5/2t^2

200 = 1/2t^2

400 = t^2

20s = t

Hence

The body will take 20 second   to cover a distance of 1km.

Hope it helps you