Question

• An object with a mass of 3.50 kg moves in a straight line on a frictionless horizontal surface with a speed of 2.0 m/s. Find the kinetic energy and the net work done on the object to make it reach this speed if it started from rest.

Answer 1

Answer

Mass m=3.5kg

Speed v=2.0 m/s

So kinetic energy

$K=0.5mv^2=0.5\times3.5\times2\\=3.5J$

According to work energy theorem

$\Delta K=work done$

Here final speed is zero due to rest

So

Work done=$K=7J$