An irregular piece of metal weighs 10.00g in air and 8.00g whaen submerged in water
(a) Find the volume of the metal and its density.
(b) If the same piece of metal weighs 8.50g when immersed in a particular oil. What is the density of the oil?

Answer

A, B, C

Explanation

(a) Relative density of metal
`=("weight in air" )/("change in weight in water" )=(10/2)=5`
`:.` Density of metal`=5rho_(w)=5000kg//m^(3)`
Now, volume `=("mass")/("density")`
`=(10xx10^(-3))/(5000)`
`2xx10^(-6)m^(3)`
(b) change in weight
upthrust on `100%` volume of solid
or, `Delta w =V_(s)rho_(l)g`
`:. Delta w prop rho_(l)`
`Delta w_(l)/(Delta w_(w))=(rho_(l))/(rho_(w))`
or,`rho_(l)= ((Deltaw_(i))/(Deltaw_(w))) rho_(w) =((1.5)/(2)) (1000)`
`= 750 kg//m^(3)`