lemonfish551

An antenna with a radiation efficiency (eca) of 90% has a directivity of 7.0 dB. What is its gain in decibels?

Kindly solve the below questions:

1. Assume the AC frequency is 50 Hz. Convert these phasors to signals (remember that phasor magnitudes are RMS values of the signals)

    (a) V = 115∠90V

    (b) I = 10 + 10j A

2.  Convert these signals to phasors (remember to us RMS values for the phasor magnitude)

    (a) v(t) = 230cos (314t + 20) V

    (b) i(t)  = 5cos (314t + 10) A

3. Suppose the voltage across a load is v(t) and the current drawn is i(t) where 

v(t) = 230cos (314t + 20) V

i(t)  = 5cos (314t + 10) A

   (a) calculate the complex power, real power, reactive power and apparent power.

   (b) calculate the power factor and indicate if it is leading or bagging

Let D be the region bounded by the hemisphere x² + y² + (z-1)² = 9, 1 ≤z≤ 4, and the plane z = 1. Verify the Guass divergence theorem for v=xi+yj + (z - 1)k.