Q 11-10-102JEE MainJEE Main 2020 (2 Sep, Shift 2)Easy
When the temperature of a metal wire is increased from $0^\circ\text{C}$ to $10^\circ\text{C}$, its length increases by $0.02\%$. The percentage change in its mass density will be closest to:
Answer: (A) $0.06$
Volume expansion is three times the linear expansion: $\dfrac{\Delta V}{V} = 3\times0.02\% = 0.06\%$.
Mass is unchanged, so $\rho \propto 1/V$ and the density decreases by about $0.06\%$.
Solution by Sreeraj P, M.Sc Physics