Question

a)Name the law which relates the current in a conductor and the potential
difference across it?
(b) State the above law and express it mathematically.
(c) Three resistors R1, R2and R3have the values 5 Ω, 10 Ω, 30 Ω, respectively
are connected in parallel which have been connected to a battery of 12 V.
Calculate (i) the current through 10 Ω resistor,
(ii) the total circuit resistance.
(iii) total current in the circuit.​

Answer 1

A-Ohm's Law deals with the relationship between voltage and current in an ideal conductor. The potential difference (voltage) across an ideal conductor is proportional to the current through it. The constant of proportionality is called the "resistance", R.

B-THE ANSWER IS IN THE PICTURE

C-V=12V

R1, R2 and R3  are connected in parallel.

(a) Current through R1 = V/R1 = 12/5 = 2.4 A

  Current through R2 = V/R2 = 12/10 = 1.2 A

  Current through R3 = V/R2 = 12/30 = 0.4 A

(b) Total current in the circuit = 2.4 + 1.2 + 0.4 = 4 A

(c)  Total resistance in the circuit=R

     1/R = 1/R1+ 1/R2 + 1/R

 1/R = 1/5 + 1/10 + 1/30            

  1/R = 10/30

  R = 3 ohm