Question

What is weight of a block of mass 5 kg at the centre of Earth? (take g=10 $m/s^2$)

• A. 50N
• B. 100N
• C. ZERO
• D. Can’t be determined

Answer 1

The correct option is C

ZERO

For the points lying on the surface of Earth or above it we can assume the mass of Earth to be concentrated at its centre for all practical purposes. But this is not true once we go inside the surface. At the centre, all the mass of Earth surrounds the point from all directions so they would cancel out each other's effect and hence the value of 'g' at the centre will be zeto.