Question

A brass cylinder weighs 90 gm in air. If the density of brass is 9 gm cc-1, the weight of the
cylinder in water is
A) 80 gm
B) 81 gm
c.10 gm
D) 90 gm​

Answer 1

80 gm is the weight of cylinder in water.

Explanation:

The mass of cylinder in air is 90 gm.

the density of brass in water is 9 gm cc⁻¹

The density of water is 1 gm cc⁻¹

The volume of the body is $\frac{mass}{density}$

⇒volume =$\frac{90}{9}=10 cc$

The weight of body in water is difference in density* volume*g

Therefore, mass of body in water is density*volume.

mass in water = $(density difference*volume)$ = $(9-1)*10=80gm$

Therefore the mass of cylinder in water is 80 gm