A steel sphere of mass 5 g is projected vertically downward at 10 m/s from a height of 19.5 m. It sinks into sand by 50 cm. Taking g = 10 m/s², the loss in mechanical energy is:

Question

Accepted Answer

1.25 J. Taking the final rest point (0.5 m inside sand) as reference, total initial mechanical energy = m*g*(19.5+0.5) + (1/2)*m*u^2 = 0.005*10*20 + 0.5*0.005*100 = 1.0 + 0.25 = 1.25 J, all lost when the sphere stops.

A steel sphere of mass 5 g is projected vertically downward at 10 m/s from a height of 19.5 m. It sinks into sand by 50 cm. Taking g = 10 m/s², the loss in mechanical energy is:

Solution

Related JEE Main Physics questions