A gas flows through a square conduit. At one point along the conduit, the conduit sides are 0.1 m, velocity is 7.55 m/sec and mass density of gas is 1.09 kg/m3. At a second point, the conduit sides are 0.25 m, velocity is 2.02 m/sec. The mass flow rate and density at second point respectively are:
Mass flow rate,Q=ρ1A1V1
=1.09×(0.1)2×7.55
=0.0823 kg/sec
Now from conservation of mass principle
ρ1A1V1=ρ2A2V2
0.0823=ρ2×(0.25)2×2.02
ρ2=0.652 kg/m3