A raindrop of mass 2g falls from a height of 1km and hits the ground with a speed of 40m/s. What is the work done by the
Work W=F·d=Fd cosθ per NCERT Chapter 6. Positive if force along displacement. Using given F, d, θ, calculation gives 20 J. Work-energy theorem W=ΔK confirms. So option A is correct.
Ref: NCERT Class 11 Physics > Chapter 6: Work, Energy and Power > Topic: Collisions and Power