Question

Stu wanted to calculate the resistance of a light bulb connected to a 4.0-V battery, with a resulting current of 0.5 A. He used the formula R = VI and obtained an answer of 2 . Was Stu’s answer correct? How do you know?

Answer 1

Answer:

Sample Response: Stu's answer was incorrect. According to Ohm's law, R = V/I. This is the equation that should be used to obtain the correct answer, which is 8 ohms.

Explanation:

Straight copied and pasted from edge. 2020

Answer 2

Answer:

The answer is not correct.

Explanation:

Stu's answer is not correct, the equation to use is known as the law of ohm. In which the voltage is defined as the product of the current by the resistance, then we will see this equation.

$V = I*R\\where:\\I = current [amp]\\R = resistance [ohm]\\V = voltage [volts]$

In order to find resistance, this term is found multiplying the current on the right side of the equation, therefore the current will be divided on the left side of the equation.

$R=\frac{V}{I} \\replacing:\\R=\frac{4}{0.5} \\R=8[ohms]$

That is the reason that the result found by Stu is not correct.