Biology Forums - Study Force

Particle A (mass = m, charge = Q) and B (mass = m, charge = 5 Q) are released from rest with the distance between them equal to 1.0 m. If Q = 12 C, what is the kinetic energy of particle B at the instant when the particles are 3.0 m apart?
 a. 8.6 J
  b. 3.8 J
  c. 6.0 J
  d. 2.2 J
  e. 4.3 J

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[Ques. 2] A particle (charge = Q) is kept in a fixed position at point P, and a second particle (charge = q) is released from rest when it is a distance R from P. If Q = +2.0 mC, q = 1.5 mC, and R = 30 cm, what is the kinetic energy of the moving particle after it has moved a distance of 10 cm?
 a. 60 kJ
  b. 45 kJ
  c. 75 kJ
  d. 90 kJ
  e. 230 kJ

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[Ques. 3] Three identical point charges (+2.0 nC) are placed at the corners of an equilateral triangle with sides of 2.0-m length. If the electric potential is taken to be zero at infinity, what is the potential at the midpoint of any one of the sides of the triangle?
 a. 16 V
  b. 10 V
  c. 70 V
  d. 46 V
  e. 44 V

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[Ques. 4] Four identical point charges (+6.0 nC) are placed at the corners of a rectangle which measures 6.0 m  8.0 m. If the electric potential is taken to be zero at infinity, what is the potential at the geometric center of this rectangle?
 a. 58 V
  b. 63 V
  c. 43 V
  d. 84 V
  e. 11 V

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[Ques. 5] A +4.0-C charge is placed on the x axis at x = +3.0 m, and a 2.0-C charge is located on the y axis at y = 1.0 m. Point A is on the y axis at y = +4.0 m. Determine the electric potential at point A (relative to zero at the origin).
 a. 6.0 kV
  b. 8.4 kV
  c. 9.6 kV
  d. 4.8 kV
  e. 3.6 kV

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[Ques. 6] Identical 2.0-C charges are located on the vertices of a square with sides that are 2.0 m in length. Determine the electric potential (relative to zero at infinity) at the center of the square.
 a. 38 kV
  b. 51 kV
  c. 76 kV
  d. 64 kV
  e. 13 kV

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[Ques. 7] Point charges of equal magnitudes (25 nC) and opposite signs are placed on (diagonally) opposite corners of a 60-cm  80-cm rectangle. If point A is the corner of this rectangle nearest the positive charge and point B is located at the intersection of the diagonals of the rectangle, determine the potential difference, VB  VA.
 a. 47 V
  b. +94 V
  c. zero
  d. 94 V
  e. +47 V

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[Ques. 8] Three charged particles are positioned in the xy plane: a 50-nC charge at y = 6 m on the y axis, a 80-nC charge at x = 4 m on the x axis, and a 70-nc charge at y = 6 m on the y axis. What is the electric potential (relative to a zero at infinity) at the point x = 8 m on the x axis?
 a. +81 V
  b. +48 V
  c. +5.8 V
  d. 72 V
  e. 18 V

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[Ques. 9] Several charges in the neighborhood of point P produce an electric potential of 6.0 kV (relative to zero at infinity) and an electric field of 36 N/C at point P. Determine the work required of an external agent to move a 3.0-C charge along the x axis from infinity to point P without any net change in the kinetic energy of the particle.
 a. 21 mJ
  b. 18 mJ
  c. 24 mJ
  d. 27 mJ
  e. 12 mJ

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[Ques. 10] An alpha particle (m = 6.7  1027 kg, q = +3.2  1019 C) has a speed of 20 km/s at point A and moves to point B where it momentarily stops. Only electric forces act on the particle during this motion. Determine the electric potential difference VA  VB.
 a. +4.2 V
  b. 4.2 V
  c. 9.4 V
  d. +9.4 V
  e. 8.4 V

1)  d

2)  b

3)  d

4)  c

5)  c

6)  b

7)  d

8)  b

9)  b

10)  b

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