Pakistan MCQs

A floating object displaces enough fluid for buoyancy to equal its weight.
The submerged fraction depends on relative density.

Hydrostatic pressure is ρgh.
P=1000×10×5 = 50,000 Pa.

Torque is rF sinθ.
τ=2×20×sin30° = 20 N·m.

Viscosity represents internal friction between layers.
More viscous fluids resist deformation more strongly.

The pressure is 100/0.01 = 10,000 Pa.
Output force is 10,000×0.20 = 2000 N.

Angular velocity is angular displacement divided by time.
ω=10/2 = 5 rad/s.

Streamline or laminar flow has ordered layers.
Turbulent flow contains irregular fluctuations and mixing.

Buoyant force equals ρVg.
F=1000×0.03×10 = 300 N.

Angular acceleration is change in angular velocity over time.
α=(16-4)/3 = 4 rad/s².

Cohesive molecular forces create surface tension.
It makes a liquid surface behave like a stretched membrane.

For floating equilibrium, submerged fraction equals object density divided by fluid density.
750/1000 = 0.75.

Linear speed is v=rω.
V=0.5×8 = 4 m/s.