Question

a body starts from rest and pick up the velocity of 15 metre per second in 3 seconds find the acceleration a metre per second second kilometre per hour square​

Answer 1

Answer:

$\boxed{\sf Acceleration = 5 \ m/s \ \ \ OR \ \ \ 18 \ km/h}$

Given:

Initial velocity (u) = 0 m/s

Final velocity (v) = 15 m/s

Time taken (t) = 3 sec

To Find:

Acceleration in m/s² and km/h²

Explanation:

$\sf From \ 1^{st} \ equation \ of \ motion:$

$\sf \boxed{\bold{v = u + at}}$

$\sf \implies 15 = 0 + a(3)$

$\sf \implies 3a = 15$

$\sf \implies a = \frac{15}{3}$

$\sf \implies a = 5 \ m/s$

To Convert m/s to km/h:

$\sf \frac{m}{s} = \frac{\frac{1}{1000} \times km}{\frac{1}{3600} \times h}$

$\sf \frac{m}{s} = \frac{36 \cancel{00} \times km}{10 \cancel{00} \times h}$

$\sf \frac{m}{s} = \frac{18 \times km}{5 \times h}$

$\sf 1 \ m/s = \frac{18}{5} \ km/h$

$\therefore$

$\sf \implies 5 \ m/s = \frac{18}{\cancel{5}} \times \cancel{5} \ km/h = 18 \ km/h$