Question

A particle falls towards earth from infinity. The velocity with which it reaches earth's surface is.

• A. v=2gR
• B. $v=\sqrt{gR}$
• C. $v=\sqrt{2gR}$
• D. v=R/g

Answer 1

Answer: (C)

$v=\sqrt{2gR}$

Answer 2

$\frac{1}{2} m \nu^2 - \frac{GMm}{R} = 0$