Question

A lamp of resistance 20 ohm is joined to a battery of 12V . Find the value of resistance to be connected in series with the lamp in order to get a current of 0.5A

Answer 1

in order to get 0.5A current we have to connent the lamp in series which get final value of resistence 24ohm

Answer 2

Answer:

Resistance, R' = 4 Ω

Explanation:

It is given that,

Resistance of the lamp, $R=20\ \Omega$

Voltage, V = 12 V

Current in the circuit, I = 0.5 A

The resistor connected in series is R'. So, the equivalent resistance is given by the sum of the equivalent resistances.

Using Ohm's law :

$V=IR_{eq}$

12 = 0.5 × (20 + R' )

R' = 4 Ω

Hence, the resistance that is connected in series is 4 Ω.