9. A 1kg ball is thrown up with a speed of 9.9m/s . calculate the work done by its weight in 1s .
Answer = mass of object=1 kg
velocity=9.9m/s
Work done =kinetic energy=1/2 mv2
=1/2 *9.92*1
=49.005 J
velocity=9.9m/s
Work done =kinetic energy=1/2 mv2
=1/2 *9.92*1
=49.005 J