Home
Class 12
PHYSICS
How much audio power is necessary to ful...

How much audio power is necessary to fully modulate a 100 kW carrier if the modulation system is 75% efficient?

Text Solution

AI Generated Solution

To find the audio power necessary to fully modulate a 100 kW carrier with a modulation system that is 75% efficient, we can follow these steps: ### Step 1: Understand the given data - Carrier power (Pc) = 100 kW = 100,000 W = \(10^5\) W - Modulation efficiency = 75% = 0.75 ### Step 2: Determine the modulation index Since the modulation system is 75% efficient, we can consider the modulation index (m) to be equal to 0.75. ...
Promotional Banner

Similar Questions

Explore conceptually related problems

A 300W carrier is modulated to a depth 75%. The total power in the modulated wave is

A 100 V carrier wave is mode to vary betqeen 160 and 40 V by a modulating signal . What is the modulation index ?

A carrier wave of peak voltage 12 V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation intex of 75 % ?

The efficient transmission of signals is achieved by superimposing electrical audio signals on a high frequency carrier wave (the process is known as modulation). When the amplitude of high frequency carrier wave is changed in accordance with the intensity of modulating signal, it is called amplitude modulation. The extent to which the amplitude of carrier wave is changed by the signal is described by modulation factor. It is given as m="Amplitude change of carrier wave"/"Amplitude of unmodulated carrier wave" Let a carrier wave is represented by V_c=V_c cos omega_ct Let the modulation factor be m, the maximum change in amplitude of carrier wave is mV_c So, modulating signal can be represented as v_m=mV_c cosomega_mt So, the amplitude of modulated wave is =V_c+mV_c cosomega_m t Using this value, the instantaneous voltage of modulated wave is E=V_c cos omega_c t+ (mV_c)/2 cos (omega_c+omega_m)t + (mV_c)/2 cos (omega_c-omega_m ) t The above wave contains three frequencies namely, f_c, f_c+f_m and f_c-f_m . The frequencies f_c+f_m and f_c-f_m are called side band frequencies , USB and LSB respectively. The fraction of total power carried by side band frequencies is

A block and tackle system has V.R. = 5. Rohan exerts a pull of 150 kgf. What is the maximum load he can raise with this pulley system if its efficiency = 75% ?

The efficient transmission of signals is achieved by superimposing electrical audio signals on a high frequency carrier wave (the process is known as modulation). When the amplitude of high frequency carrier wave is changed in accordance with the intensity of modulating signal, it is called amplitude modulation. The extent to which the amplitude of carrier wave is changed by the signal is described by modulation factor. It is given as m="Amplitude change of carrier wave"/"Amplitude of unmodulated carrier wave" Let a carrier wave is represented by V_c=V_c cos omega_ct Let the modulation factor be m, the maximum change in amplitude of carrier wave is mV_c So, modulating signal can be represented as v_m=mV_c cosomega_mt So, the amplitude of modulated wave is =V_c+mV_c cosomega_m t Using this value, the instantaneous voltage of modulated wave is E=V_c cos omega_c t+ (mV_c)/2 cos (omega_c+omega_m)t + (mV_c)/2 cos (omega_c-omega_m ) t The above wave contains three frequencies namely, f_c, f_c+f_m and f_c-f_m . The frequencies f_c+f_m and f_c-f_m are called side band frequencies , USB and LSB respectively. If modulation factor is 100% , the amplitude change of carrier wave is

A carrier wave of peak voltage 12 V is used to transmit a message signal. The peak voltage of the modulating signal in order to have a modulation index of 75% is

A carrier wave of peak voltage 12 V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation index of 75% ?

The antenna current of an AM transmitter is 8A when only the carrier is sent but increases to 8.96A when the carrier is modulated sinusoidally . The percentage modulation is