Question

A storage battery has e.m.f.15 volts and
internal resistance 0.05 ohm. Its terminal
voltage when it is delivering 10 ampere
is
​

Answer 1

Given :

EMF of battery = 15 Volts

Internal resistance = 0.05 Ω

Current flow in circuit = 10 A

To Find :

Terminal voltage of battery.

Solution :

■ For a cell of internal resistance r, the emf is given by : [e = V + Ir]

• e denotes emf of battery
• V denotes potential difference
• I denotes current flow
• r denotes internal resistance

By substituting the given values;

➛ e = V + Ir

➛ 15 = V + (10)(0.05)

➛ 15 = V + 0.5

➛ V = 15 - 0.5

➛ V = 14.5 volts

■ Additional Information :

• The resistance of a conductor is a measure of the opposition offered by the conductor to the flow of current.
• This opposition is due to frequent collision of the electrons with the atoms of the conductor.
• Inside the cell, the current flows from negative plate to positive plate while outside the cell from positive plate to mega plate. But during charging of cell, thus direction is reversed$.$