H2 Physics Question

LastRide7 SG

Can someone help me explain on how do I go about approaching this question?
I don't need the solutions, just the explanations will do.

An object hangs from a spring balance. The balance registers 30N in air, 20N when this object is immersed in water and 24N when it is immersed in another liquid of unknown density. Determine the density of the liquid.

Richan80 SG

the upthrust on the object in water is 10N.

upthrust is = volume of liquid displaced (i.e. volume of object if object completely immersed) x gravitational acceleration x density of liquid

so...

10N = vol of obj x 9.81 x 1000 kg/m^3

so you can find vol of obj.

then upthrust in liquid of unknown density is 6N.

6N = vol of obj (from above) x unknown density (call it D) x 9.81

so can find the unknown density liao.