Biology Forums - Study Force

An electron is sent at high speed toward a gold nucleus (charge +79e). What is the electrical force acting on the electron when it is 1.7  1014 m away from the gold nucleus? (e = 1.6  1019 C, ke = 8.99  109 Nm2/C2)
 a. 6.3E+1 N
  b. 1.1E12 N
  c. 5.0E+3 N
  d. 6.7E+6 N
  e. 8.0E5 N

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[Ques. 2] A series RLC circuit in a radio is in resonance with AM 700 kHz. If the radio station is changed to AM 2100 kHz, by what factor must the capacitance be multiplied to again achieve resonance?
 a. 9
 b. 3
  c. 1
  d. 1/3
  e. 1/9

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[Ques. 3] In a thundercloud there may be an electric charge of +30 C near the top of the cloud and 30 C near the bottom of the cloud. These charges are separated by about 4.00 km. What is the electric force between these two sets of charges? (ke = 8.99  109 Nm2/C2)
 a. 5.1E+11 N
  b. 1.3E+20 N
  c. 5.1E+5 N
  d. 2.0E+9 N
 e. 3.2E+13 N

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[Ques. 4] A series RLC AC circuit is at resonance. It contains a resistor of 18.7 , a capacitor of 0.460 F and an inductor of 70.9 mH. If an effective (rms) voltage of 41.0 V is applied, what is the effective (rms) current when the circuit is in resonance?
 a. 1.25 A
  b. 2.19 A
  c. 3.84 A
  d. 0.672 A
  e. 7.68 A

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[Ques. 5] The constant ke, which appears in Coulomb's law formula, is equivalent dimensionally to which of the following?
 a. N/m/C
  b. N/C
  c. N/m2/C2
  d. N/C2

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[Ques. 6] An AC series circuit contains a resistor of 30.0 , a capacitor of 1.22 F and an inductor of 154 mH. What frequency should be used to create a resonance condition in the circuit?
 a. 3.49E+2 Hz
  b. 8.48E+2 Hz
  c. 9.21E+2 Hz
  d. 3.67E+2 Hz
  e. 7.35E+2 Hz

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[Ques. 7] If the size of the charge value is tripled for both of two point charges maintained at a constant separation, the mutual force between them will be changed by what factor?
 a. 9
  b. 3
  c. 1/3
  d. 1/9
  e. 1

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[Ques. 8] A series RLC circuit is connected across a 240-Hz AC source, where Vmax = 140 V, R = 480 , C = 0.250 F, and L = 3.25 H. What is the average power delivered to this circuit?
 a. 77.9 W
 b. 1.78 W
 c. 3.56 W
 d. 0.890 W

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[Ques. 9] If the distance between two point charges is doubled, the mutual force between them will be changed by what factor?
 a. 4
  b. 2
  c. 1/2
  d. 1/4
  e. 1

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[Ques. 10] A circuit consists of an AC audio amplifier, a resistor, and a speaker, all in series. The amplifier puts out an alternating voltage of 16.0 V (rms), the resistance of the resistor is 10.0 , and the speaker has a resistance of 11.9 . What is the time-averaged power delivered to the speaker?
 a. 21.5 W
  b. 30.5 W
  c. 6.35 W
  d. 8.69 W

1)  a

2)  e

3)  c

4)  b

5)  c

6)  d

7)  a

8)  d

9)  d

10)  c

I know this sounds cliche, but I was thinking the same thing for each of these. Thanks for confirming :)

I'm sure ;) Thanks for your honesty