Static Fluids Homework, Physics homework help

[kieraecivres]

Here's the question: "a solid block is suspended from a spring scale. When the block is in the air, the scale reads 35.0 N, when it is immersed in water the scale reads 31.1 N, and when it is immersed in oil, the scale reads 31.8 N.
A.) What's the density of the block?
B.) What's the density of the oil?"

I know you probably have to use either archemedes' formula or newtons second law to figure this out, but I don't know how.

[Kino]

Think about what information you need to answer the question.

What could Archimedes' Principle tell you when the block is immersed in the liquids?

What does the fact that it's the same block tell you about both cases?

What is the relationship between weight and mass?

You'll have to look up the density of water.

[boit]

For the sake of simplicity assume the density of air is zero.

[boit]

I am poor at presenting my work but the answers are close to the real value
A.) 8.9*10^3kgm^-3
B.) 0.8*10^3kgm^-3

This post has been edited by boit on Oct 6 2011, 02:31 PM