Question

If the Earth-Sun distance is held constant and the mass of the Sun is doubled, then the period of revolution of the earth around the Sun will change to ____________.

Options

• (1/2) year

• `1//sqrt2` year

• `sqrt2`

• 2 years

Answer 1

If the Earth-Sun distance is held constant and the mass of the Sun is doubled, then the period of revolution of the earth around the Sun will change to `1//sqrt2` year.

Explanation:

`"T" = 2pi sqrt("r"^3/"GM")`

`therefore "T" prop 1/sqrt"M"`     `therefore "T"_2/"T"_1 = sqrt("M"_1/"M"_2)`

`therefore "T"_2 = 1 xx sqrt(1/2)  "year"`