Electrical Engineering Answers

1.Write v(t) = 10sin(377t+60) as a phasor .

2.Find the pf if v(t) = cos(100t+30) i(t) = sin(100t).

3.Draw the phasor diagram for v(t) = 10cos(100t) i(t) = cos(100t+30)

4.For a power load of 1KW with pF = 0.707 lagging. Draw power triangle.

5.Three capacitors of 10μFare in series. Find equivalent capacitance.

6.A transformer has 600KVA rating. Calculate power delivered at pF = 0.85.

7.Three impedances 1,j1 and j2 are in series. Calculate equivalent resistance and reactance.

8.A source of 10 Volts has an internal impedance of 10-j10. Find the load for maximum power.

For position vector, R=X ax+Y ay+Z az, show that

a) div R=3

b)curl R=0

c)curl[R/R^3]=0

If the potential function,V is given by V=(x^3)y-x(y^2)+3z

convert the following equation written in cartesian coordinate in to an equation of cylindrical coordinates x^3-2x^2-6z=4-2y^2

a closed surface is defined in spherical coordinates by 3<r<5,0•1π<0<•3π,1•2π<Fi<1•6π find the volume enclosed. hint (dv=r^2sina ddr,da,dfi)

1.    Two sides of a square are on the line x + 10y – 10 = 0 and x + 10y – 5 = 0. Find the area of the square.

Generate a Cosine signal and one unit step signal using MATLAB codes

1. Write MATLAB codes to find the EVEN and ODD parts of the signal x(t)=e^2t

2. Write MATLAB codes to find the energy and power of the signal x(t)= 10 sin(10 πt)

Write a Matlab program to perform Amplitude scaling, Time Scaling and Time Shifting on the signal x(t)= 1+t, for t=0 to t=2.( Imagine arbitrary scaling factor)

X(t) = t-2 for -2<=t<=0

= 2-t for 0<=t<=+2

= 0 otherwise

Find out the Energy and power of the signal. Also check whether the signal is energy signals and power signals