Question

. An object changes its velocity from 10 m/s to 20 m/s having mass 50 kg find the work done in terms of change in kinetic energy.

Answer 1

Answer:

Final velocity 20m/s

Initial velocity 10m/s

mass 50 kg

work done =1/2mv square - 1/2 mu square

Solve this and u will get answer as 3750J

Answer 2

Given,

Mass, m = 50 kg.

Initial velocity, u=10 m/s

Final velocity, v=20 m/s

Work done = change in K.E.

$\boxed{\sf \: w = K.E_f-K.E_i}$

$\sf \implies \: w = \frac{1}{2} \times m {v}^{2} - \frac{1}{2} m {v}^{2}$

$\sf \implies \: w = \frac{1}{2} m( {v}^{2} - {u}^{2} )$

$\sf \implies \: w = \frac{1}{2} \times 50( {20}^{2} - {10}^{2} )$

$\sf \implies \: w = 25(300)$

$\boxed{\sf \implies \: w = 7500 \: J}$