RC Parallel Circuits

Question 1

The total capacitance of a parallel circuit is always ______ than the largest capacitor.

Answer 1

The total capacitance of a parallel circuit is always greater than the largest capacitor.

Question 2

What formula is used to find Total capacitance (Ct) in a parallel circuit?

Answer 2

Total capacitance (Ct) in a parallel circuit is equal to the sum of each capacitor’s value.

Ct = C1 + C2 + C3….

Question 3

What is Capacitive Reactance (Xc) in a parallel circuit?

Answer 3

Capacitive Reactance (Xc) in a parallel circuit is the opposition to current flow.

Question 4

Xc is measured in _____ and is dependent on the value of capacitance and the ______ of the circuit.

Answer 4

Xc is measured in ohms and is dependent on the value of capacitance and the frequency of the circuit.

Question 5

To find capacitive reactance in an RC parallel circuit, what formula is used?

Answer 5

Xc = 1 ÷ (2)(pie)(f)(C)

Example is for C1

Question 6

What is the formula for total capacitive reactance (Xct)?

Answer 6

Question 7

As frequency increases, Xc ______.

Answer 7

As frequency increases, Xc decreases.

Question 8

As capacitance increases, Xc _______.

Answer 8

As capacitance increases, Xc decreases.

Question 9

R and Xc are not exactly the same quantity they oppose current flow differently. The resulting opposition to current flow is called_______. The unit of measure is ______.

Answer 9

The resulting opposition to current flow is called impedance (Z). The unit of measure is ohms.

Question 10

What is the formula for total impedance (Zt) in an RC parallel circuit?

Answer 10

Question 11

what is the difference between between Zt formulas in series and parallel circuits?

Answer 11

Question 12

Name the steps and formulas needed to solve for total and branch currents in this circuit?

Answer 12

1. Calculate total capacitance. Ct = C1 + C2
2. Find total capacitive reactance. Xct = 1 ÷ (2)(pie)(f)(Ct)
   * Note: Don’t forget to convert µF 6 places to the left
3. Determine total resistance. Rt = R1 + R2
4. Solve for total impedance.
5. Solve for total current. It = Ea ÷ Zt
6. Calculate branch currents. Ir = Ea ÷ Rt, Ic = Ea ÷ Xct
7. To check the results, calculate total current.

Question 13

Reactive power in an RC parallel circuit equals the power generated by _______.

Answer 13

the capacitor only