b. Derive the expression of coefficient of coupling in
terms of mutual inductance a»4self-inductance.

Ktubtect 11/25/1015. ( westions.com

14 a.. The output voltage appearing across an electronic power converter is shown. in (6)
figure. Find RMS and average value ofv(t) if Vm = 100 V and a 60°

0. Explain how sinusoidal voltages and current are represented in phasor form (4) 15 a.
Express the phasorin time domain '1(1)' after carryingrequired computation in . (5)
(4671*132 9 ३७४४०

` (2८-25)2-/2) =

phasor form 1.2)
0. Sketch how die parameters of a series RLC circuit vary with frequency. Define 'Q'
(5) Factor and bandwidth of a series resonant circuit?
16 8, Prove the instantaneous power consumed by a pure inductor is zero. (3)

b. A series RTC circuit with L— 25 mH and C = 70 PF has a lagging phase angle (7)
30° at f—320 Hz. At what frequency will the phase angle be 40° leading

PART- ^
Answer ೫01111 Questions (17 018 and 19 or 20)
17 a. The Power input and line current of three phase induction motor is 15 kW and (6) 25A

respectively. Find the readings of two watt meters connected to measure the motor input
power. Assume three phase supply voltage is 400V
b. Explain phase sequence of three phase system. (4)
-OR
18 a. Figure below shows a watt meter connection in three phase balanced load is (6) connected

to balanced three phase supply. Prove that wattmeter reading is proportional to reactive
power consumed by the load.