Explanation

• Heat is a form of energy associated with the motion of molecules in a substance.
• As molecules vibrate, rotate, and collide, they transfer energy from one another, resulting in the sensation of heat.

Explanation

• Earth is the biggest of all the terrestrial planets.
• It has temperature, weather, atmosphere and many other factors.
• Its surface 30% is covered with land and 70% with water.
• It has only one moon called Luna.

Explanation

Nuclear fusion is a process where two or more light nuclei (atomic nuclei with a small number of protons and neutrons) combine to form a single, heavier nucleus.

This process releases energy, as the resulting nucleus has a higher binding energy than the original nuclei.

Explanation

Gamma-rays have the highest penetrating power, making them suitable for treating tumors that are deep inside the body.

Gamma-rays are high-energy electromagnetic waves with frequencies higher than X-rays, and they can travel several centimeters into tissue before being absorbed.

Explanation

The gravitational field of Earth is a vector field that points towards the center of the Earth.

It representing the direction of the gravitational force that the Earth exerts on objects near its surface.

This means that the gravitational field is directed towards the Earth, pulling objects towards its center.

Explanation

The motion of a falling ball towards Earth is due to the gravitational force.

Gravitational force is the force that attracts the ball towards the Earth, causing it to accelerate downwards.

Explanation

A microwave oven heats food by using electromagnetic radiation at a specific frequency

That resonates with the water molecules in the food, causing them to vibrate and generate heat.

This process of energy transfer due to matching frequencies is called resonance. 

Explanation

The negative gradient of electric potential is called Electric field intensity. 

Gradient:

In general, a gradient represents the rate of change of a function for a given variable.

In the context of electric fields, the gradient of electric potential indicates how quickly the potential changes as you move in a particular direction. 

Negative gradient:

The "negative" part signifies that the electric field points in the direction of decreasing potential. 

Explanation

Explanation

The number of loops in stationary waves depends on the wavelength of the waves. 

A longer wavelength means fewer loops fit within a given length, and vice versa, so the number of loops is directly related to the wavelength.