Pakistan MCQs

Thermal radiation can travel through vacuum.
Its intensity increases strongly with absolute temperature.

The ideal gas model simplifies real gas behavior.
It works best at low pressure and high temperature.

Rotational dynamics gives τ=Iα.
τ=3×4 = 12 N·m.

Stress measures internal force intensity.
It may be tensile, compressive, or shear.

Opposing torques subtract.
The net magnitude is 15-9 = 6 N·m.

Strain compares deformation with original dimension.
It is dimensionless.

Universal gravitation applies to any pair of masses.
The force acts along the line joining their centers.

Young's modulus measures material stiffness.
A larger value means less strain for a given stress.

Gravitational field strength is g=F/m.
Its unit is N/kg, equivalent to m/s².

Use F=Gm₁m₂/r².
F=6.67×10^-11×2×3 = 4.002×10^-10 N.

Gravitational potential is a scalar quantity.
It represents work per unit mass associated with position.

Gravitational force varies inversely with distance squared.
Doubling distance multiplies force by 1/2² = 1/4.