Calculating ga on Earth and an Asteroid using F=-kx Formula

[imy786]

Homework Statement

You have to do a measurement of ga using a different method. You have in your equipment a standard 2 kg mass and an accurate spring balance. You know that on Earth, at a place with g = 9.81 m s−2, that a mass of 20g produced an extension of 100 mm. On the asteroid surface, you suspend your standard kilogram mass from the spring and measure an extension of
110 mm.

Calculate ga.

Homework Equations

F=-kx

The Attempt at a Solution

do i use this forumal F=-kx twice,
first when his on the Earth then when on asteroid.
and then eqating this value to f=mg

[need help]

 

[hage567]

Well if you found ga in another part of the question already, why don't you just try your method and see if you get the same answer?!