Question

A train accelerates uniformly from 36km/hr to 72 km/hr in 20s.find dis travelled

Answer 1

v=72km/hr
u=36km/hr
t=20 sec
$a = \frac{v - u}{t} = \frac{72 - 36}{20} = \frac{36}{20} = \frac{9}{5} \\ s = ut + \frac{1}{2} at {}^{2} = 36 \times 20 + \frac{1}{2} \times \frac{9}{5} \times \frac{9}{5} = 720 + \frac{81}{50}$
=720+1.62=721.62m