Explanation

Light is a form of energy.

Light is actually energy made of small particles called photons.

Explanation

In a dry cell, the electrolyte is a paste of ammonium chloride mixed with zinc chloride.

This paste allows the flow of electric current by enabling the movement of ions within the cell.

Explanation

The distance between the optical center and the principal focus is called the focal length of the lens.

while

A negative focal length indicates that the system diverges light.

Explanation

Electric fire alarms often use the principle of expansion, where materials expand when heated due to a fire, triggering the alarm.

As the temperature rises during a fire, the metal or bimetallic strips in the alarm expand, activating the electrical circuit to sound the alarm.

Explanation

The solar energy that reaches the Earth annually is far more than the world's total energy consumption, with estimates suggesting it is more than 10,000 times the current global energy needs.

This vast amount of energy highlights the potential of solar power as a renewable energy source.