Question

A resistance of ____ ohm should be connected in series to a 15 ohm resistance to produce 0.4 A current across a circuit with potential difference 12 V

Answer 1

current-0.4 A
p.d-12V
current= p.d÷resistance.
resistance - 12÷0.4
- 30
resistance to be connected - 30-15
- 15 ohm