According to work energy theorem
W done by gravity +W done by resistive force =1/2 mv^2
W done by gravity = mgh = 2*10^-3*10*1000=20J
1/2mv^2= 1/2*2*10^3*(50)^2=2.5J
Thus, Work done by resistive force=1/2mv^2-work done by gravity
=20-2.5 J
= 17.5 J ( It can take negative value since it is a resistive force acting opposite to the direction of motion of the drop)
Hope you get it !!!
A drop of mass 2.0 g falls from a cliff of height 1.0 km. It hits the ground with a speed of 50.0 m/s. The work done by resistive force is
1. -10j
2. -12.50j
3. -15.5j
4. -17.50j
solution:- I think change in kinetic energy can give me work done. But how to get resistive force.
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