Given, density of liquid, ρl=1.2gcm−3 density of oil =ρ0=0.9gcm−3
As we know that, At same level, pressure remains same. ∴p0+ρ0g(h+15)=p0+ρlg(15+15) where, p0 is atmospheric pressure. ∴ρ0(h+15)=ρl30 ⇒0.9(h+15)=1.2×30 ⇒3(h+15)=4×30 ⇒3h+45=120 ⇒3h=75 ⇒h=25cm ∴ Difference in level of oil and liquid =25−15=10cm