PPSC MCQs

Metals transfer heat efficiently from the flame to food.
This makes cooking faster and more even.

A raised object has energy because of its position in a gravitational field.
This energy can convert to kinetic energy as it falls.

Kinetic energy is the energy of motion.
It depends on the object's mass and speed.

The fan's motor converts electrical energy into rotation.
Some energy is also lost as heat and sound.

Chemical reactions inside a battery create an electric potential.
The stored chemical energy is converted into electrical energy.

Solar cells use the photovoltaic effect.
They convert light directly into electrical energy.

A microphone detects sound vibrations.
It converts them into corresponding electrical signals.

A loudspeaker uses electrical signals to move a diaphragm.
The diaphragm produces sound waves in air.

Heat flows from a hotter body to a cooler body.
It is energy in transit rather than a material substance.

Temperature indicates how energetic particle motion is on average.
It determines the direction of heat flow.

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.