Question

Two resistors each of resistance 2 ohm and 4 ohm connected in parallel. Which of these consume more power.​

Answer 1

Answer:

R

1

=R

2

=2Ω

P

1

=?

P

2

P

1

=?

V=12V

P

2

=?

Series

(i) R=R

1

+R

2

=2+2=4Ω

I=

R

V

=

4

12

=3A

∴P

1

=VI=12×3=36W

Parallel

(ii)

R

1

=

R

1

1

+

R

2

1

=

2

1

+

2

1

=1Ω

I=

R

V

=

1

12

=12A

∴P

2

=VI=12×1=12W.

Hence,

P

2

P

1

=

12

36

=

1

3

=3:1

Answer 2

Explanation:

Potential difference (V) = 4 V

12 Ohm and 2 Ohm resistors are connected in parallel.

The voltage across each component of a parallel circuit remains the same. Hence, the voltage across 2 Ohm resistor will be 4 V.

Power consumed by 2 Ohm resistor is given by

P= V2/R

P = 42/2

P = 8 W