A small body of superdense material, whose mass is twice the mass of the earth but whose size is very small compared to the size of the earth, starts form rest at a height `H lt lt R` above the earth's surface, and reaches the earth's surface in time `t`. then `t` is equal to

A small body of super dense material, whose mass is half the mass of the earth (but whose size is very small compared to the size of the earth), starts from rest at a height H above the earth’s surface, and reaches the earth’s surface in time t. Calculate time t assuming that H is very small compared to the radius of the earth. Acceleration due to gravity near the surface of the earth is g.