Question

A body starts from rest and is found to cover 3 m during the 5th second of its motion. Find the acceleration if it uniformly accelerated.

Answer 1

Step 1: Given data

Distance covered by the body in 5th second, S = 3 m.

Since, it covers the distance of 3m in 5th second, Hence, time taken is 1 second to cover that distance.

Time = 1 second

Initial velocity, u = 0 m/s.

Step 2: Finding the velocity

Let, the uniform acceleration of the body is $am/s^2.$

Now,

$\mathrm{Velocity}=\frac{\mathrm{Distance}}{timetakentocoverthisdis\tan ce}=\frac{3}{1}=3m/s.$

Step 3: Finding the acceleration

From the newton's first equation of motion;

$v=u+at.$…….(1)

Where v and u are the final and initial velocities respectively, a is uniform acceleration, and t is total time.

From equation (1).

$a=\frac{v-u}{t}=\frac{3-0}{5}=0.6m/s^2.$

Therefore, the uniform acceleration of the body is $0.6m/s^2.$