Electrical Engineering

All Q&A

Explain with proper expression

Modulation index
Bandwidth required for transmission of FM

23 November, 2024

The modulation index in AM wave is defined as the ratio between amplitude of the modulating signal and amplitude of the carrier signal. The mathematical representation is given below

The maximum deviation allowed in an FM broadcast system is 75 kHz. If the modulating signal is a single tone sinusoid of 10 kHz, find the bandwidth of the FM signal. What will be the change in the bandwidth, if the modulating frequency is double? Determine the bandwidth when modulating signal amplitude is also double.

23 November, 2024

Given that ∆f=75KHz and fm=10KHz According to the Carson’s thumb rule the bandwidth BW=2(∆f+fm )=2(75+10)=170KHz

1. a. State sampling theorem. What is Nyquist rate of sampling?

b. What is pulse amplitude modulation

c. What is meant by flat top sampling? Why is it more preferred than natural sampling?

d. Explain the demodulation of PAM signal using a hold circuit

e. What is the bandwidth required for transmission of PAM signal?

23 November, 2024

a. The sampling theorem state that A band limited signal of finite energy, which has no frequency components higher than fm Hz, is completely described by its sampled values less than or equal to 1/(2fm ) second apart.

At t=0, the instantaneous value of a 50 Hz, sinusoidal current is 5 Amp and increases in magnitude further. Its R.M.S value is 10 Amp.

Write the expression for its instantaneous value
Find the current at t=0.01 and t=0.015 sec.
Sketch the waveform indicating this value.

23 November, 2024

The R.M.S value of sinusoidal current is IR.M.S=10 Amp, thus the peak value of current Imax=√2 ×IR.M.S=10√2 Amp.

For the circuit shown bellow, determine the current i₁,i₂,i₃ using nodal analysis

23 November, 2024

Considering two nodes V1 and V2, we have (V1-24)/2+V1/6+V2/8=3 Or 16V1+3V2=360 …(1) The difference between two nodes is

For the circuit shown below, find the potential difference between a and d:

23 November, 2024

Applying KVL in 1st mesh, we have 4I1-3=0 Or I1=3/4 Amp. Vab=2I1=2×3/4=3/2 V

State and explain Thevenins theorem. Find the Thevenins equivalent of the circuit of Fig.18(a) as shown at terminal XY.

Fig. 18(a)

23 November, 2024

Thevenin’s theorem states that any two terminal bilateral linear d.c circuits can be replaced by an equivalent circuit consisting of a voltage source and a series resistor.

Subjects

Design of Reinforced Concrete Structures surveying Compiler Design Computer Graphics and Multimedia Basic Electrical Engineering Mobile computing

Browse Streams