Question

The height at which the weight of a body becomes one third of its weight on the surface of earth is (R is the radius of earth)

• A. $\frac{R}{3}$
• B. $0.732 R$
• C. $0.414 R$
• D. $\frac{R}{6}$
• E. $\frac{R}{10}$

Hint:

Logic Tip: Do not use the approximation formula $g_h = g(1 - 2h/R)$ unless $h$ is specifically stated to be very small compared to $R$ (typically $< 5%$). Since the weight changes by a massive factor (1/3), the exact formula must be used.

Answer 1

The Correct Option is B