A body weighed 250N on the surface. Assuming the earth to be a sphere of uniform mass density, how much would it weigh half way down to the centre of earth?
A.
240N
B.
210N
C.
195N
D.
125N
Answer: Option D
Explanation:
At depth, d=R/2 gd=g(1-d/R)=g(1-(R/2)/R)=g/2 New weight = mg/2=250/2=125N.