Question

What will happen to value of g if we go inside the earth and what will happen to the value of g if we go at the center of the earth .why explain brefly?

Answer 1

As we go inside the earth the distance between centre and object decreases and hence the value of g should increase but it is not so the mass of earth is concentrated at centre so as we go down the effective mass keeps on decreasing and effect of mass is much more than effect of distance so vale of g decreases and at center it becomes 0

If the relation: g' = g( 1 - {x/R}) where g' is apparent gravity, g is acceleration due to gravity on the face of the Earth, x is depth (distance of body from centre of Earth), and R is the radius of Earth then we can say as we go in towards the Earth centre( say it's core),x goes on decreasing untill it becomes zero. Thus at the centre of the Earth x=0 and g' becomes zero.