ISCET DC Circuits Fundamentals 3

Question 1

Thevenin's theorem replaces a complex network with which equivalent circuit?

Accepted Answer

A voltage source in series with a resistance

Answer

Thevenin's theorem reduces any linear two-terminal network to a single voltage source (Vth) in series with a resistance (Rth).

Question 2

What is the conductance of a 25Ω resistor?

Accepted Answer

0.04 S

Answer

Conductance G = 1/R = 1/25 = 0.04 siemens (S).

Question 3

A current of 3A flows through a 4Ω resistor for 10 seconds. How much energy is dissipated?

Accepted Answer

360 J

Answer

Energy W = P × t = I²Rt = 3² × 4 × 10 = 9 × 4 × 10 = 360 J.

Question 4

Norton's theorem converts a network to which equivalent?

Accepted Answer

A current source in parallel with a resistance

Answer

Norton's equivalent circuit consists of a short-circuit current source (In) in parallel with the Norton resistance (Rn).

Question 5

In a current divider with two parallel resistors R1=4Ω and R2=12Ω and total current IT=8A, what current flows through R1?

Accepted Answer

6A

Answer

I1 = IT × R2/(R1+R2) = 8 × 12/(4+12) = 8 × 0.75 = 6A.

(ISCET) International Society of Certified Electronics Technicians Practice Test