Question

A piece of wax weights x g in air. A piece of metal is found to weigh y g in water. it is both together weigh z g in water. The specific gravity of wax is (z > y)

• A. $\frac{x}{y}$
• B. $\frac{y}{x}$
• C. $\frac{x}{x-(z-y)}$
• D. $\frac{x}{x-(y-x)}$

Answer 1

The correct option is C $\frac{x}{x-(z-y)}$

$V_{wax}{\rho }_{wax}=xgram\left(1\right)$

In water, weight of wax:

$x-V_{wax}{\rho }_{water}x-\frac{x}{{\rho }_{wax}}{\rho }_{water}$

Total weight$=z$

$z=x-x\left(\frac{{\rho }_{water}}{{\rho }_{wax}}\right)+y\frac{{\rho }_{water}}{{\rho }_{wax}}=\frac{x}{x-z+y}$