The weight of an object at the centre of the earth of radius R is

The weight of an object at the centre of the earth of radius R is

  1. zero
  2. infinite
  3. R times the weight at the surface of the earth
  4. 1/R2 times the weight at surface of the earth

Answer

The weight of an object, w = mg

At the centre of the earth, acceleration due to gravity g is zero. It is given by

g' = g(1 - h/R)

where h = distance from surface of the earth to centre of the earth.

At the centre of the earth, h = R

g’ = 0

So, w = m × 0 = 0

The correct option is A.