The emf phasor in FIGURE EX32.2 is shown at t=15ms.

a. What is the angular frequency ω? Assume this is the first rotation.

b. What is the instantaneous value of the emf?

Short Answer

Expert verified

The angular frequency ωis 244rad/sand instantaneous value of the emf is-10V.

Step by step solution

01

Part (a) Step 1: Given information

We are given that time t=15ms, Eo=12Vand =150(as the phasor rotates anticlockwise towards X-axis)

02

Part (a) Step 2: Calculation

As we know that-

E=E0cos(ωt+)

ωt=180+ωt=180+30ωt=210 (as phasor rotates anticlockwise)

Now converting degrees into radian

210=210πrad180=7πrad6

Now,

ωt=7πrad6ω(15×10-3)=7πrad6ω=244rad/s

03

Part (b) Step 1: Given information

We are given that-

E0=12V=150

04

Part (b) Step 2: Calculation

As we know that peak valueE0=12V will occur when ωt=0

So now in the expression,

E=E0cos(ωt+)E=12Vcos(0+150)E=-10V

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Most popular questions from this chapter

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a 2.1mH inductor, and a 550nF capacitor. It is connected to a 50V rms oscillating voltage source with an adjustable frequency. An oscillating magnetic field is observed at a point 2.5mm from the center of one of the circuit wires, which is long and straight. What is the maximum magnetic field amplitude that can be generated?

FIGURE Q32.1shows emf phasors a, b, and c.

a. For each, what is the instantaneous value of the emf?

b. At this instant, is the magnitude of each emf increasing, decreasing, or holding constant?

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