Explanation

Handheld metal detectors commonly use batteries ranging from 1.5V (AA) up to 9V.

This low voltage powers the device for portability and safety.

Explanation

Polyisoprene is the synthetic version of natural rubber.

It has similar properties.

It is commonly used to make rubber products.

Explanation

Explanation

The energy stored in coal is classified as chemical energy.

It is released during combustion when the chemical bonds in the coal are broken.

This energy is harnessed for heating and electricity generation.

Explanation

An electric field does work on a charge, causing it to gain or lose energy (kinetic or potential).

A magnetic field can change the direction of a moving charge.

Explanation

Concave mirrors focus light into a strong, parallel beam, making them ideal for headlights and searchlights.

They reflect light from the bulb placed at their focus point, projecting it forward efficiently.

Explanation

A derived quantity is obtained from fundamental quantities (like mass, length, and time).

Force = Mass × Acceleration (Newton’s Second Law), so it is derived from mass, length, and time.

Explanation

A hygrometer is an instrument used to measure the moisture content or humidity level in the air.

It often used in weather forecasting and environmental studies.

Explanation

Gauss → Unit of magnetic induction (CGS system)

Tesla → SI unit of magnetic induction

Weber/Ampere·meter → This is a unit of magnetic permeability, not magnetic induction

Explanation

Materials that block the flow of electrons are called insulators.

They have high resistance and prevent electrical current from flowing through them.

Such as rubber or glass.