An object is allowed to fall from a height above the earth

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

An object is allowed to fall from a height

R

above the earth, where

R

is the radius of earth. Its velocity when it strikes the earth's surface, ignoring air resistance, will be : (1)

2\sqrt{gR}

(2)

\sqrt{gR}

(3)

\sqrt{\frac{gR}{2}}

(4)

\sqrt{2gR}