In a circuit involving resistance and capacitance,which of the following choices would result in the longest time constant?
A)R = 100 Ω,C = 30 μF
B)R = 300 Ω,C = 150 μF
C)R = 75 Ω,C = 75 μF
D)R = 200 Ω,C = 200 μF

Question

Quizplus · Accepted Answer

The time constant (in seconds) for a circuit with resistance R (in ohms) and capacitance C (in farads) is given by RC. Therefore, the longest time constant would be the option with the highest value of RC. 
For option A, RC = (100 Ω)(30 μF) = 3 ms. 
For option B, RC = (300 Ω)(150 μF) = 45 ms. 
For option C, RC = (75 Ω)(75 μF) = 5.625 ms. 
For option D, RC = (200 Ω)(200 μF) = 40 ms. 
Therefore, option B has the longest time constant.

In a Circuit Involving Resistance and Capacitance,which of the Following