Question

The resistance of a lamp that draws 0.5A of current when it is operated by a 12V battery will be Ω

Answer 1

According to ohm's law
V=IR
Or R=V/I
R=12/0.5
R=24ohm

Answer 2

According to Ohm's Law, the resistance, current and voltage are related as:

V = IR
⇒
R = V/I

V is given to be 12 Volts.
I is given to be 0.5 Ampere

So, resistance will be:

R = 12/0.5 = 24 ohms