Question

There is a circuit with 2 resistors in series and a cell of 3.0v.what is the resistance across the first resistor if the current through it is 0.2A and pd across 2.0v also whats the pd for second circuit?

Answer 1

Answer:

The resistance of the  first resistor is, R₁ = 10 Ω

Explanation:

Given data,

The potential of the cell v = 3 V

The current through the first resistor, I = 0.2 A

The P.D across the first resistor, v₁ = 2.0 V

Let R₁, and R₂ be the resistance of the resistors,

Since the voltage across the series connection is,

                                   v = v₁ + v₂

Substituting the values

                                    3 V = 2 V + v₂

∴                                       v₂ = 1 V

Hence, the P.D across the second resistor is, v₂ = 1 V

The resistance of the first resistor is,

                                   R₁ = v₁ / I

                                        = 2 V / 0.2 A

                                         = 10 Ω

Hence, the resistance of the  first resistor is, R₁ = 10 Ω