Question

A block of mass 2kg is lying on the friction less table.A force of 80 N is applied on it for 12 S .calculate its kinetic energy.​

Answer 1

Acceleration of the block , a=F/m=8/2=4m/s

2

Using equation of motion, S=ut+

2

1

​

at

2

=0(10)+0.5(4)(10)

2

=200 m

Now using , v

2

−u

2

=2aS, v

2

−0

2

=2(4)(200)

or v

2

=1600

Thus, KE =

2

1

​

mv

2

=

2

1

​

×2×1600=1600 J