How to Calculate Resistance in a Circuit

What is the formula to calculate resistance in a circuit?

Given that a light bulb is connected to two batteries, each with a voltage of 1.5V, and a student measures the current flowing through the light bulb to be 2A, what is the resistance of the light bulb?

Answer:

R = 0.75 ohms

Resistance in a circuit can be calculated using Ohm's Law, which states that voltage (V) is equal to current (I) multiplied by resistance (R). The formula for Ohm's Law is:

V = IR

Given the values in the scenario, we can substitute them into the formula to find the resistance of the light bulb. The voltage (V) is 1.5V from each battery, and the current (I) is 2A. Plugging these values into the formula:

R = V / I

R = 1.5 / 2

R = 0.75 ohms

Therefore, the resistance of the light bulb in this circuit is 0.75 ohms.