In the circuit above, the resistors all have the same resistance. The battery, wires, and ammeter have negligible resistance. A closed switch also has negligible resistance.

Closing which of the switches will produce the greatest power dissipation in R2?


S1 only

S2 only

S1 and S2 only

S1 and S3 only

S1, S2, and S3

without a diagram,...

To determine which switch configuration will produce the greatest power dissipation in resistor R2, we need to analyze the circuit and understand how the power is distributed.

Looking at the circuit, we see that there are three switches: S1, S2, and S3. To simplify the analysis, let's consider each switch combination separately.

1. S1 only: If we close only S1, current will flow through both R1 and R2 in series. Since the resistors have the same resistance, the current will split equally between them. Therefore, the power dissipation in R2 will be equal to the power dissipation in R1.

2. S2 only: If we close only S2, current will flow through both R2 and R3 in series. Again, the resistors have the same resistance, so the current will split equally between them. Therefore, the power dissipation in R2 will be equal to the power dissipation in R3.

3. S1 and S2 only: If we close both S1 and S2, the circuit becomes parallel. Now, the current will only flow through R2, resulting in the maximum power dissipation in R2. This is because all the current from the battery will be directed through R2.

4. S1 and S3 only: If we close both S1 and S3, the circuit becomes a series configuration. Now, the current will flow through R1 and R2 in series. Similar to case 1, the power dissipation in R2 will be equal to the power dissipation in R1.

5. S1, S2, and S3: If we close all three switches, the circuit becomes a combination of series and parallel connections. However, since S1 is closed, the highest power dissipation will still occur in R2, as the current will flow primarily through it.

Therefore, the correct answer is "S1 and S2 only." Closing both S1 and S2 will result in the greatest power dissipation in resistor R2.