Question

A body has a weight of $10kg$ on the surface of the Earth. What will be its mass and weight when taken to the centre of the Earth?

• A. $10$ kg, zero
• B. zero, zero
• C. $10$ kg, $10$g
• D. zero, $10$g

Answer 1

Answer: (A)

$10$ kg, zero

Mass is constant and hence will be $10kg$.
W=mg and $g=\frac{4\pi G{\rho }_0}{3}(1-\frac{d}{R})$ where R is the radius of earth, ${\rho }_0$ is the density of earth, d is the depth.
At the center of earth $d=R$, and hence $g=0$ and $W=0$