Question

plz give correct ans and process​

Answer 1

Answer :

The velocity of the body after next 5 seconds is 40m/s

and the distance covered at that time is 162.5m

Given :

• A body accelerates uniformly from 10m/s to 25m/s in 5s

To Find :

• The velocity of the body after next 5 seconds
• The distance covered by the body in that time

Solution :

We are given the following

initial velocity , u = 10m/s

final velocity , v = 25m/s

time taken , t = 5s

From the equations of motion we have :

$\sf{v = u + at} \\ \\ \sf \implies v - u = at \\ \\ \sf \implies a = \frac{v - u}{t} \\ \\ \implies \sf a = \frac{25 - 10}{5} \\ \\ \sf \implies a = \frac{15}{5} \\ \\ \bf \implies a = 3 m {s}^{ - 1}$

acceleration is 3m/s²

Now

$\implies \sf v = u + at \\\\ \sf \implies v_o = 25 + 3\times 5 \\\\ \sf \implies v_o = 25 + 15 \\\\ \bf \implies v_o = 40 m/s$

Thus the velocity of the body after next 5 seconds is 40m/s

again ,

$\sf \implies {v}^{2} - u^{2} = 2as \\\\ \sf \implies \dfrac{{v}^{2} - u^{2}}{2a}= s \\\\ \sf \implies s = \dfrac{{v}^2 - u^2 }{2a} \\\\ \sf {Now \: \: considering \: \: final \: \: velocity \: v =40 m/s }\\ \sf { and \: \: initial \: \: velocity \: , u = 25m/s \: \: we \: \: have : } \\\\ \sf \implies s = \dfrac{40^2 - 25^2}{2\times 3}\\\\ \sf \implies s = \dfrac{1600 - 625}{6}\\\\ \sf \implies s = \dfrac{975}{6} \\\\ \sf \implies s = \dfrac{325}{2}\\\\ \bf \implies s = 162.5m$

Thus the distance covered in that time is 162.5m