Question

If the radius of the earth decreases by 1% and its mass remains the same, then the acceleration due to gravity ___________

(a) Increases by 1%

(b) Decreases by 1%

(c) Increases by 2%

(d) Decreases by 2%

This question was addressed to me in an internship interview.

My question is based upon Intensity of Gravitational Field topic in chapter Mechanical Properties of Solids of Engineering Physics I

Answer 1

Right option is (c) Increases by 2%

The best explanation: g=GM/R^2

For constant G and M

∆g/g×100=2∆R/R×100=-2(-1)%=+2%

The value of g increases by 2%.