NEET 2015 Physics and Chemistry Paper

Let r0 and rT be densities of glycerin at 0∘C and T∘C respectively. Then,
ρT=ρ0(1−γ∆T)
where γ is the coefficient of volume expansion of glycerine and ∆T is rise in temperature.
‌

ρT

ρ0

=1−γ∆T⇒γ∆T=1−‌

ρT

ρ0

Thus, ‌

ρ0−ρT

ρ0

=γ∆T
Here, γ=5×10−4K−1 and ∆T=40∘C=40K
∴ The fractional change in the density of glycerin
=‌

ρ0−ρT

ρ0

=γ∆T=(5×10−4K−1)(40K)=0.020