Home
Class 12
PHYSICS
A piece of brass (Cu and Zn) weighs 12.9...

A piece of brass (Cu and Zn) weighs `12.9g` in air. When completely immersed in water, it weighs `11.3g`. Then relative densities of Cu and Zn are `8.9 and 7.1` respectively. The mass of copper in the alloy is

Text Solution

Verified by Experts

Let `m_(1)g` arid `m_(2)g` be the mass of Cu and Zn respectively in alloy
`:.` Volume of Cu = `m_(1)/8.9 cc`
and volume of Zn= `m_(2)/7.1 cc`
`:.` Total volume of alloy= `[m_(1)/8.9 + m_(2)/7.1]cc`
Now, loss of wt. in water = thrust due to water
`implies (16.8 - 14.7)g = [m_(1)/8.9 + m_(2)/7.1]xx1 g`
`implies 2.1= m_(1)/8.9 + m_(2)/7.1`....(i)
Also, the total mass of alloy
`m_(1) + m_(2) =16.8g`
Solving (i) & (ii) we get,
`m_(1)=9.345g` and `m_(2)=7.455g`
Promotional Banner

Similar Questions

Explore conceptually related problems

A Piece of brass (alloy of zinc and copper) weighs 12.9 g in air. When completely immersed in water it weighs 11.3 g . What is the mass of copper contained in the alloy ? Specific gravity of zinc and copper are 7.1 and 8.9 respectively.

What mass of lead will weigh as much as 8 gm of iron when both are immersed in water ? (given specific gravities of iron and lead are 8 and 11 respectively).

A piece of solid weighs 120 g in air, 80 g in water and 60 g in a liquid. The relative density of the solid and that of the liquid are respectively

A piece of solid weighs 120 g in air ,80 g in water and 60 kg in a liquid . The relative density of the solid and that of the liquid are respectively

A piece of solid weighs 120 g in air, 80 g in water and 60 g in a liquid, then the relative density of the solid, and that fo liquid are

An object weighs 9.8 N in air and 9.0 N when fully immersed in water. How much is the buoyant force on the object?

A piece of steel has a weight w in air, w_(1) when completely immersed in water and w_(2) when completely immersed in an unknown liquid. The relative density (specific gravity) of liquid is

An empty density bottle weighs 22g. When completely filled with water it weighs 50g. When completely filled with brine solution it weighs 54g. The density of brine solution is _______

A sample of metal weighs 210 g in air , 180 in water , and 120 in liquid . Then , relative density of

A body weighs 500 gf in air and 300 g f when completely immersed in water. Find (a) the apparent loss in the weight of the body, (b) the upthrust on the body (c ) the volume of the body.