Network Engineering MCQs — Test 1

Correct Answer: B. B. False
Explanation: The above statement is false. Crossover network circuit is made of filter circuits having a cut off frequency equal to crossover frequency. Crossover networks make use of the principle that the inductive reactance increases with increase in frequency (Xl = 2πfL), and the capacitive reactance decreases with increase in frequency (Xc = 1/2πfC).

Correct Answer: B. B. Crossover
Explanation: The crossover network is shown in the figure. A crossover network contains a woofer and a tweeter. The job of splitting the frequencies and sending them off to each speaker in the system is done by a crossover network.

Correct Answer: C. C. Crossover frequency
Explanation: Crossover network circuit is made of filter circuits having a cut off frequency equal to crossover frequency. The point where the curve of woofer output crosses the curve of Tweeter output is known as the crossover frequency.

Correct Answer: A. A. C = 1 / 2πfc∊2rl
Explanation: A low pass filter can be made with the series reactance of L and shunt reactance of C. Thus, the equation for capacitance in crossover network is C = 1 / 2πfC√2RL. Where, C = Capacitance in farads RL = Loudspeaker impedance in ohms fC = crossover frequency in Hz

Correct Answer: A. A. L = ˆ?2rl / 2πfc
Explanation: A LPF (low pass filter) can be made with the series reactance of L and shunt reactance of C. Thus, the equation for inductance in crossover network is L = √2RL / 2πfC. Where, L = Inductance in Henry RL = Loudspeaker impedance in ohms fC = crossover frequency in Hz

Correct Answer: A. A. 20 hz to 500 hz
Explanation: The crossover frequency for a woofer and tweeter circuit is where the woofer output curve crosses the tweeter output curve. The range of woofer for 3 way speaker system is 20 Hz to 500 Hz. The range of woofer for two way speaker systems is 20 Hz to 1000 Hz and range of tweeter for two way speaker system is 1000 Hz to 20,000 Hz.

Correct Answer: B. B. 5000 hz to 20,000 hz
Explanation: The range of tweeter for 3 way speaker system is 5000 Hz to 20,000 Hz. The range of woofer for three way speaker systems is 20 Hz to 500 Hz and the range of squawker for three way speaker system is 500 Hz to 5000 Hz.

Correct Answer: B. B. C = 28.13 μf, l = 3.6 mh
Explanation: L = √2RL / 2πfC C = 1 / 2πfC√2RL Substitute the given values in the above equation. C = 1 / 2π × 500 × 1.4 × 8 C = 28.13 μF L = 1.4 × 8 / 2π × 500 L = 11.2 / 1000π L = 3.6 mH