Question

(i) Three 3 resistors are connected in parallel and the whole

combination is connected in series with 5 resistor. Draw the required

arrangement.

(ii) Find the equivalent resistance

(iii) The whole combination is connected across voltage source of 12 V.

Draw the arrangement.

(iv) Find the current drawn by the voltage source.

(v) Find the current through 5 resistor.​

Answer 1

Explanation:

The diagram of three resistors connected in series combination is shown.

R

1

,R

2

and R

3

are the three resistors.

I = electric current flowing through the circuit

V = the potential difference supplied by the battery

Applying the Ohm’s law to the entire circuit, we have

V=IR

On applying Ohm’s law to the three resistors separately, we further have

V

1

=IR

1

V

2

=IR

2

and V

3

=IR

3

The total potential difference across a combination of resistors in series is equal to the sum of potential difference across the individual resistors. That is,

V=V

1

+V

2

+V

3

Therefore, IR=IR

1

+IR

2

+IR

3

or

Equivalent resistance of the combination, R=R

1

+R

2

+R

3