ISCET DC Circuit Analysis 4

Question 1

Thevenin's theorem replaces a complex two-terminal network with:

Accepted Answer

A voltage source in series with a resistance

Answer

The Thevenin equivalent is Vth (open-circuit voltage) in series with Rth (equivalent resistance).

Question 2

To find the Thevenin resistance of a circuit containing only independent sources, you should:

Accepted Answer

Deactivate all sources and measure resistance at the terminals

Answer

Rth is found by deactivating all independent sources and calculating the resistance seen from the open terminals.

Question 3

What is the maximum power transfer condition in a DC circuit?

Accepted Answer

Load resistance equals source resistance

Answer

Maximum power is transferred when RL = Rs (or RL = Rth), per the maximum power transfer theorem.

Question 4

A 50Ω load is connected to a Thevenin equivalent circuit of 100V and 50Ω. What power is delivered to the load?

Accepted Answer

50W

Answer

I = 100/(50+50) = 1A; P = I²×RL = 1²×50 = 50W.

Question 5

In the Norton equivalent circuit, the Norton current is equal to:

Accepted Answer

The short-circuit current at the terminals

Answer

Norton current (IN) is measured by placing a short circuit across the output terminals and measuring the resulting current.

(ISCET) International Society of Certified Electronics Technicians Practice Test