If density of earth increased 4 times and its radius become half of what it is, our weight will

Options

A. remain same
B. be four times its present value
C. be halved
D. be doubled

Answer

D

Explanation

Weight = mg
`therefore W prop g` as m is constant and `g=(4)/(3) pi RG rho " " g prop rho R`
`therefore (g')/(g)=(4rho)/(rho)xx(R )/(2R)=2`
`therefore g'=2g " " therefore` The weight will be doubled.