Question

A current of 4a flows through a 12v car headlight bulb for 10 min. how much energy transfer occurs during this time .

Answer 1

R =v/I
=12÷4=3ohms
E=I^2RT
=4×4×3×(10×60)
=16×1800
=28800 joules or 28.8kj

Answer 2

According to the Question

I = 4 A

V = 12 v

Time = 10 minutes

Convert into Hours

$\bf\hugefrac{10}{60} = \frac{1}{6} hour$

Total energy consumed

= V × I × T

= 12V × 4A × 1/6h

= 8Wh

= 8 × 10^-3 kWh

1kWh = 3.6 × 10^6 Joule

Total energy transferred

= 8 × 10^-3 × (3.6 × 10^6) Joule

= 28800 Joule

= 28.8 kJ