Key Topic 14: RC Time Constants-1

Question 1

3-14B1: What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the supply voltage?

A. An exponential rate of one.
B. One time constant.
C. One exponential period.
D. A time factor of one.

Answer 1

B. One time constant.

Question 2

3-14B2: What is the meaning of the term “time constant of an RC circuit”? The time required to charge the capacitor in the circuit to:

A. 23.7% of the supply voltage.
B. 36.8% of the supply voltage.
C. 57.3% of the supply voltage.
D. 63.2% of the supply voltage.

Answer 2

D. 63.2% of the supply voltage.

Question 3

3-14B3: What is the term for the time required for the current in an RL circuit to build up to 63.2% of the maximum value?

A. One time constant.
B. An exponential period of one.
C. A time factor of one.
D. One exponential rate.

Answer 3

A. One time constant.

Question 4

3-14B4: What is the meaning of the term “time constant of an RL circuit”? The time required for the:

A. Current in the circuit to build up to 36.8% of the maximum value.
B. Voltage in the circuit to build up to 63.2% of the maximum value.
C. Current in the circuit to build up to 63.2% of the maximum value.
D. Voltage in the circuit to build up to 36.8% of the maximum value.

Answer 4

C. Current in the circuit to build up to 63.2% of the maximum value.

Question 5

3-14B5: After two time constants, the capacitor in an RC circuit is charged to what percentage of the supply voltage?

A. 36.8%
B. 63.2%
C. 86.5%
D. 95%

Answer 5

C. 86.5%

Question 6

3-14B6: After two time constants, the capacitor in an RC circuit is discharged to what percentage of the starting voltage?

A. 86.5%
B. 13.5%
C. 63.2%
D. 36.8%

Answer 6

B. 13.5%