How to Calculate Resistance of a Lamp with a 12V Battery?

What information do we need to calculate the resistance of a lamp?

We need to know the voltage of the battery and the current flowing through the lamp.

Answer:

The resistance of the lamp will be 30 ohms.

To calculate the resistance of the lamp, we can use Ohm's Law which states that resistance (R) is equal to voltage (V) divided by current (I). In this case, we are given that a 12V battery supplies a current of 0.4A to the lamp.

So, using the formula R = V / I, we can plug in the values: R = 12V / 0.4 A R = 30 ohms

Therefore, the resistance of the lamp is 30 ohms when connected to a 12V battery with a current flow of 0.4A.