Q.
The force acting on a window of area 50cm×50cm of a submarine at a depth of 2000m in an ocean, the interior of which is maintained at sea level atmospheric pressure is (Density of sea water =103kgm−3, g=10ms−2)
Here, h−2000m, ρ=103kgm−3, g=10ms−2
The pressure outside the submarine is P=Pa+ρgh
where Pa is the atmospheric pressure
Pressure inside the submarine is Pa
Hence, net pressure acting on the window is gauge pressure
Gauge pressure, Pg=P−Pa=ρgh =103Kgm−3×10ms−2×2000m=2×107pa
Area of a window is A=50cm×50cm=2500×10−4m2
Force acting on the window is F=PgA =2×107pa×2500×10−4m2=5×106N