Question

Explain electrical energy and derive its formula.

Page 87 Chapter - 4.Electricity

Answer 1

Electrical energy is a form of energy resulting from the flow of electric charge. Energy is the ability to do work or apply force to move an object. In the case of electrical energy, the force is electrical attraction or repulsion between charged particles. Electrical energy may be either potential energy or kinetic energy , but it's usually encountered as potential energy, which is energy stored due to the relative positions of charged particles or electric fields.
Derivation :
Electric power, P = work done by electric current /time
P = w /t
Now, acc to law of conservation of energy
Work done by current = energy consumed
E = W = P x t

Answer 2

The energy consumed by an electric circuit to flow current through it is referred as electrical energy. This energy is provided by the battery to every electric charge. The work required to keep the charge Q in motion by the battery of voltage V is

W=VQ

From the definition of electric current,

Q=It

Therefore, W=VIt

According to Ohm’s law, V=IR

$\underline{\boxed{\sf I²Rt }}$

Thus, the current flowing through the resistor R for time t is I, the electrical energy consumed to is W which is converted into heat energy.