A body of mass 2 ~kg thrown vertically from the ground with a velocity of 8 ~ms ⁻¹ reaches a maximum height of 3 ~m . The work done by the air resistance is (acceleration due to gravity =10 ~ms ⁻² )

Step-by-step solution

Initial energy of particle = 1 2 m v^2= 1 2 2 8^2=64 ~J Final energy of particle at maximum height =m g h=2 10 3=60 ~J Work done against air friction = Loss of energy =64-60=4 ~J