Question

If R1 , R 2 , R3 are of 30 Ω, 10Ω and 5 Ω respectively. Calculate:

i) Total resistance in circuit

ii) If the battery provides a voltage of 6V , find current in circuit.

iii) Current in each resistor.

Answer 1

1) TOTAL RESISTANCE IN CIRCUIT----

45 OHM

Answer 2

Answer:

i)

The resistance of the 5Ω, 10Ω, 30Ω resistors connected in parallel is

1/R = 1/R1 + 1/R2 + 1/R3

= 1/5 + 1/10 + 1/30

= 6+3+1 / 30

= 10/30

1/ R = 1/3

R = 3 ohm

∴the total resistance of the given circuit is 3 Ohms.

ii)

The total current can be calculated using the Ohm's law as the value of voltage (V) is given 6V

using Ohm's law

Voltage=Current×Resistance

I = V/R

I = 6/3

I = 2 A

iii)

Current through each resistor can be calculated by applying Ohm's law given that the voltage of the circuit and the individual resistances of each resistor is already given.

Current through 5Ω resistor = V/R = 2/5 = 0.4 A

Current through 10Ω resistor = V/R = 2/10 = 0.2 A

Current through 30Ω resistor = V/R = 2/30 = 0.066 A