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## Homework Statement

A bar suspended in air weighs 1.75 N

The same bar weigs only 1.4 N when suspended in water.

Calculate;

a. upthrust

b. density of the bar

## Homework Equations

D = m/v

F = m*a

## The Attempt at a Solution

a[/B].

Upthrust is 1.75 N - 1.4 N = 0.35 N

**b**.

Assuming density of water is 1x10

^{3}kg m

^{-3}

and weight of bar displaces that amount of water.

So

volume 1.75 N of water = 1.75 N / (1x10

^{3}* g) = 1.78 m

^{3}

Density of bar = m/v = 1.75 N / 1.78 m

^{3}= 0.98 N m

^{-3}

which has to be wrong, surely, or the bar would float . . .

Help!

Thank you.