7. The same ac voltage is applied across a resistor and a capacitor, and the sam

Question

7. The same ac voltage is applied across a resistor and a capacitor, and the same rms current exists in each. Do both dissipate the same average power? 8. The inductance in the drawing has a value of L = 7.1 mH What is the resonant frequency f0 of this circuit? 9. The drawing shows four situations in which a positively charged particle Is moving with a velocity vthrough a magnetic field B. In each case, the magnetic field is directed out of the screen toward you, and the velocity is directed to the right. In only one of these drawings is the magnetic force Fphysically reasonable. Which one is ? 10. Two circular current carrying loops of wire are shown in the drawing. The Inner loop has a radius of RoarKI carries a current to, while the outer loop has a radius of 2Ro and carries a current of 41o. The currents are in opposite directions. If Ro = 0.20 m and to Io = 2.1 A, determine the magnitude and direction of the net magnetic field at the center of the two loops.

Explanation / Answer

7) no since capacitor on average dissipates no power since for it phi = 90

8)

2 pi f0 = 1/sqrt( LC)

2*pi*f = 1/sqrt(1.9E-6*7.1E-3)

f=1370 Hz

9)

1) v into B gives down so reasonable

2) not reasonable since not perp to v

3) not reasonable since not perp with B

4) v into B gives down, so not reasonable

10) so

Bnet = B1 - B2 = u0 I1/(2 pi r1) - u0 I2/( 2 pi r2)

= u0 I/( 2 pi r) - u0 4 I/( 2 pi 2 r) =

= - u0 I/( 2 pi r)

so in magnitude = 4*pi*10^(-7)*2.1/(2*pi*0.2)= 2.1E-6 T

Related Questions

Navigate

• Browse (All)
• Browse 7
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.