Explanation

Frictional force is a non-conservative force.

Unlike conservative forces (such as elastic spring force, gravitational force, and electric force), friction dissipates energy as heat and does not store it.

It means the work done by friction depends on the path taken.

Explanation

The electric intensity between two oppositely charged plates in the middle region is uniform.

This is because the electric field strength remains constant between the plates.

It assuming they are large and parallel, and the charges are evenly distributed.

Explanation

The formula to calculate potential difference (V) is:

V = W / Q

Where:

W = work done (in Joules)

Q = charge (in Coulombs)

Given:

W = 600 J (work done)

Q = 2 C (charge)

V = 600 J / 2 C = 300 V

So, the potential difference is 300 V.

Explanation

They act on masses is NOT a feature of electric forces.

Electric forces specifically act on charged particles.

It can be attractive or repulsive, but do not act on masses unless they are charged.

Explanation

Current (I) is defined as the rate of flow of charge (Q) with respect to time (t). The formula to calculate current is:

I = Q / t

Given:

Q = 90 C (charge)

t = 30 s (time)

I = 90 C / 30 s = 3 A

So, the current in the wire is 3 A.

Explanation

The magnitude of the current in metals being proportional to the potential difference across it, as long as the temperature of the conductor is kept constant, is known as Ohm's Law.

This law is expressed mathematically as V= I⋅R, where V is voltage, I is current, and R is resistance.

Explanation

When the length of a copper wire is doubled, the resistivity remains the same.

Resistivity is an intrinsic property of the material and does not change with the dimensions of the wire.

However, the resistance will double, as resistance is directly proportional to the length of the wire.

Explanation

The resistance of a semiconductor with a rise in temperature decreases.

This occurs because increasing temperature provides more energy to charge carriers.

It allowing them to move more freely and conduct electricity better.

Explanation

Volt x Ampere is the measure of power.

Specifically, it represents electrical power in watts (W), where power (P) is calculated using the formula 

P=V×I, with V being voltage and I being current.

Explanation

The formula Φ = 𝐵⋅ 𝐴 represents magnetic flux.

Here, 𝐵 is the magnetic flux density, and 𝐴 is the area through which the magnetic field lines pass.

It indicating the total magnetic field passing through that area.