Question

A block of mass 5kg is resting on a smooth surface at what angle a force of 20N be acted on it so that it will acquired a kinetic energy of 40J after moving 4m

Answer 1

as we know that
work done =energy =fscos thita
40J =5kg*2mper sec squre (acceleration) *cos thita(1/2mvsquare=K.E)(vsquare, =16)(vsqure2m per second square =usquare+2as) u=o and so a=
cos thita= 4
thita= cos inverse 4is the angle at which force will be. acted