Related Questions

Power gain in decibels is equal to voltage gain in decibels only when
A Input impedance is equal to output impedance
B Output impedance is zero
C Never
D Input impedance is zero
Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels.
A 35
B 75
C 95
D 105
The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels.
A 60
B 90
C 105
D 120
Noise level inside a jet air liner in normal flight is about __________ decibels.
A 80
B 100
C 125
D 145
Noise level in a quiet private business office is about __________ decibels.
A 25
B 50
C 70
D 85
Shouting by a man at his full voice corresponds to a voice level of about __________ decibels.
A 25
B 50
C 80
D 120
Noise level heard inside a bus in busy city traffic or inside a sub-way train corresponds to about __________ decibels.
A 75
B 95
C 120
D 140
A negative gain margin expressed in decibels means a/an __________ system.
A Stable
B Unstable
C Critically damped
D None of these
Conversion formula for converting amplitude ratio (AR) into decibels is
A Decibel = 20 log10 (AR)
B Decibel = 20 loge (AR)
C Decibel = 20 log10 (AR)0.5
D Decibel = 20 loge (AR)0.5
Pressure difference between two points in vessels, pipelines or in two different pipelines can be measured by a differential manometer. The pressure difference measured as the mm of water coloumn in case of mercury-water, differential manometer is equal to (where, H = difference in height of mercury column in mm).
A H
B 12.6 H
C 13.6 H
D 14.6 H

Next steps