CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

The work done to raise a mass m from the surface of the earth to a height h, which is equal to the radius of the earth, is :


A
mgR
loader
B
2 mgR
loader
C
12mgR
loader
D
32mgR
loader

Solution

The correct option is C $$\dfrac{1}{2} mgR$$
Initial potential energy at earths surface is 
$$U_i = \dfrac{-GMm}{R}$$
Final potential energy at height h = R
$$U_f = \dfrac{-GMm}{2R}$$
As work done = change in PE
$$\therefore W = U_f - U_i$$
$$= \dfrac{GMm}{2R} $$
$$(\because GM = gR^2)$$
$$= \dfrac{gR^2m}{2R} = \dfrac{mgR}{2}$$     

1259381_1618833_ans_ff63c06b4e034645bba0381c10201b32.png

Physics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image