Pakistan MCQs

Violet light has the shortest wavelength among visible colors.
It also has the highest visible-light frequency.

Wind carries away water vapor near the fabric.
This maintains a concentration difference and speeds evaporation.

Rayleigh scattering is stronger for shorter visible wavelengths.
Scattered blue light reaches observers from many directions.

Conduction transfers thermal energy through particle interactions.
It is especially important in solids.

Convection occurs when warmer fluid moves and cooler fluid replaces it.
It happens in liquids and gases.

Pascal's law states that pressure applied to a confined fluid is transmitted equally.
This allows force multiplication in hydraulic brakes.

Spontaneous heat transfer occurs from higher to lower temperature.
It continues until thermal equilibrium is approached.

Water exerts an upward buoyant force on immersed objects.
Floating occurs when this force balances the object's weight.

Archimedes' principle relates buoyant force to displaced fluid.
The upward force equals the weight of the displaced fluid.

Average speed is total distance divided by total time.
Thus, 120 ÷ 2 = 60 km/h.

A ship contains large air-filled spaces.
Its total mass spread over its volume gives an average density below water.

Gravity attracts masses toward one another.
Near Earth, it pulls objects toward the ground.