Explanation

The presence of a dielectric material between the plates of a capacitor reduces the electric field by a factor called the dielectric constant 𝐾

The electric field E in a capacitor with a dielectric is related to the field E0 without the dielectric by:

E= E0/K

​When the dielectric material is removed, the dielectric constant K becomes 1 (for vacuum or air), and the electric field reverts to its original strength, increasing by a factor of 𝐾

Thus, when the dielectric is removed, the electric field increases.

Explanation

Explanation

The electric potential at a point due to a point charge 

The formula gives Q:𝑉=𝑘/𝑄𝑟

Where:

V is the electric potential,

k is Coulomb's constant,

Q is the charge, and

r is the distance from the charge to the point where the potential is being calculated.

In this case, there are two charges: +5μC at point A and −5μC at point B.

The electric potential is a scalar quantity, meaning it can simply be added algebraically.

Explanation

One Coulomb (C) is the unit of electric charge and is defined as the amount of charge transported by a steady current of 1 Ampere (A) flowing for 1 second.

Mathematically: 

1Coulomb=1Ampere×1second

This means that if a current of 1 Ampere flows through a conductor for 1 second, the total charge transported is 1 Coulomb.

Explanation

Explanation

Explanation

The internal energy of an ideal gas is solely dependent on the kinetic energy of the molecules, which is directly related to the temperature. 

Explanation

In an isothermal process, the temperature of the system remains constant throughout.

Since this expansion occurs at a constant temperature, the internal energy is not changed (for an ideal gas, internal energy is dependent only on temperature).

The work done by the gas during expansion is not zero, and as the gas expands, the pressure decreases.

Explanation

In an adiabatic process, when the volume of a gas decreases, the temperature of the gas increases.

• In an adiabatic process, no heat is exchanged with the surroundings.
  
• When the volume decreases, the gas is compressed, and work is done on the gas.
• This work increases the internal energy of the gas, which raises its temperature.

Explanation

When a police car with its siren on moves towards a stationary listener, the frequency of the sound perceived by the listener increases.

This phenomenon is known as the Doppler effect.