Question

If a tunnel was drilled through the center of the earth and a person of weight $700N$ travelled across it.His weight at the center of the earth would be:

• A. Zero
• B. $700N$
• C. Less than $700N$ but more than zero
• D. More than $700N$
• E. Need more information

Answer 1

The correct option is A Zero

We know weight $w=mg$ ,since value of $g$ at the centre of earth is zero by $g^{\prime }=g(1-d/R)$ where $d$ is depth from earth's surface and $R$ is the radius of earth,

at centre $d=R$

so $g=0$ and therefore $w=0$