The SI unit for bandwidth is Hz. Hertz is the SI unit because bandwidth is basically frequency and the unit for frequency is Hz.
12. At the bandwidth frequency range, the value of the current I is?
A. I = Im/2
B. I = Im2
C. I = Im
D. I = Im/√2
Answer: D
At the bandwidth frequency range, the value of the current is equal to the maximum value of current divided by √2.
13. At the bandwidth frequency range, the value of the voltage V is?
A. V = Vm/2
B. V = Vm2
C. V = Vm
D. V = Vm/√2
Answer: D
At the bandwidth frequency range, the value of the voltage is equal to the maximum value of voltage divided by √2.
14. At resonance, bandwidth includes the frequency range that allows _____ percent of the maximum current to flow.
A. 33.33
B. 66.67
C. 50
D. 70.7
Answer: D
At resonance, bandwidth includes the frequency range that allows 70.2 percent of the maximum current to flow. This is because in the bandwidth frequency range, the value of the current is equal to the maximum value of current divided by √2.
15. At resonance, bandwidth includes the frequency range that allows _____ percent of the maximum voltage to flow.
A. 33.33
B. 66.67
C. 50
D. 70.7
Answer: D
At resonance, bandwidth includes the frequency range that allows 70.2 percent of the maximum voltage to flow. This is because, in the bandwidth frequency range, the value of the voltage is equal to the maximum value of voltage divided by √2.
16. Find the value of current in the bandwidth range when the maximum value of current is 50A.
A. 56.65A
B. 35.36A
C. 45.34A
D. 78.76A
Answer: B
At the bandwidth frequency range, the value of the current is equal to the maximum value of current divided by √2.
Hence I = 50/√2 = 35.36A.
17. Find the value of voltage in the bandwidth range when the maximum value of voltage is 100 V.
A. 56.65 V
B. 35.36 V
C. 45.34 V
D. 70.72 V
Answer: D
At the bandwidth frequency range, the value of the voltage is equal to the maximum value of voltage divided by √2.
Hence V = 100/√2 = 70.72V.
18. Bandwidth is the difference of_____________________ frequencies.
A. half power
B. full power
C. double power
D. wattless
Answer: A
The current for the end frequencies of bandwidth is 1/√2 times the maximum current. So, power at the end frequencies of bandwidth is half the maximum power. So, bandwidth is the difference between half-power frequencies.
19. For a sharp resonance, bandwidth is ______________
A. low
B. high
C. zero
D. infinity
Answer: A
For sharp resonance quality factor is high and the quality factor is inversely proportional to bandwidth so bandwidth is low for sharp resonance.
20. Current is maximum at __________ frequency of bandwidth.
A. left end
B. middle
C. right end
D. all end
Answer: B
Current will be maximum at a frequency that is in the middle of bandwidth.
On both sides, it decreases and is 1/√2 times the maximum current at the ends of bandwidth.
