Gas Fitter Practice Test

When two 10 ohm resistors are connected in parallel, what is the net result?

1. 0 ohms

2. 5 ohms

3. 10 ohms

4. 20 ohms

The correct answer is: 5 ohms

When two resistors are connected in parallel, the total or equivalent resistance can be calculated using the formula: 1/R_total = 1/R1 + 1/R2 In this case, both resistors have a resistance of 10 ohms each. Plugging in the values: 1/R_total = 1/10 + 1/10 This simplifies to: 1/R_total = 2/10 1/R_total = 1/5 To find R_total, you take the reciprocal: R_total = 5 ohms This demonstrates that when resistors are connected in parallel, the equivalent resistance decreases compared to the resistance of the individual resistors. In this situation, having two 10 ohm resistors in parallel results in a total resistance of 5 ohms, which aligns with the specified answer. This principle highlights how parallel resistor configurations allow for a greater total current to flow, as the pathways for current are increased, thereby decreasing the overall resistance.