Question

A force of 100 newton acts on an object of mass 10 kg for 9 sec. If the object was initially moving with the speed of 10 m/s, calculate the initial and final kinetic energy of the object. By what factor does the kinetic energy increase?

Answer 1

initial kinetic energy= ½mu²

so ½ ×10× 10²= 500 j

f = ma

a= f/m

a= 100/10

a= 10m/s²

v=u+at

v=10+ 10(9)

v= 100m/s

final kinetic energy= ½mv²

= ½×10×(100)²

=5000 j