Question

The current through a 12 V tungsten filament lamp connected to a 12 V accumulator of negligible resistance is 3 A. Calculate:
(1) The resistance of the filament
(2) The power of the lamp
(3) The electrical energy in KWH consumed in 5 hours
(Easy question, please give superb answers)

Answer 1

Explanation:

Given :

Potential difference (V) = 12 V

Electric current (I) = 3 A

Time taken (t) = 3 hours

To find :

Resistance (R)

Power (P)

Electrical power (W)

Solution :

Resistance:

=> Potential difference/Electric current

• 12/3
• 4 Ω

Power:

=> Potential difference × Electric current

• 12 × 3
• 36 W

Electrical energy:

=> Potential difference × Electric current × Time taken

• 12 × 3 × 5
• 180 Wh
• 0.18 KWh

Answers :

(1) 4 Ω

(2) 36 W

(3) 0.18 KWh