Electrostatics Problems - MCQ 21 (1) PDF

## Electrostatics Problems ### 1. Three electrons are located at the vertices of an equilateral triangle... Three electrons are located at the vertices of an equilateral triangle, one at each vertex. The length of one side of the triangle is 1.00 nm. What is the magnitude of the net electrostatic...

## Electrostatics Problems ### 1. Three electrons are located at the vertices of an equilateral triangle... Three electrons are located at the vertices of an equilateral triangle, one at each vertex. The length of one side of the triangle is 1.00 nm. What is the magnitude of the net electrostatic force on each electron? - 2.30 × 10^-10 N - 3.25 × 10^-10 N - **3.99 × 10^-10 N** - 4.60 × 10^-10 N **Difficulty:** medium ### 2. The force between a 3.0 µC and a 2.0 µ... The force between a 3.0 µC and a 2.0 µC charge is 10 N. What is the separation distance between the two charges? - 5.2 cm - 7.3 cm - 8.6 cm - **9.5 cm** **Difficulty:** medium ### 3. Point charges are placed on two of the corners... Point charges are placed on two of the corners of a triangle as shown. What is the direction of the electrostatic force felt by a 6.0 µC charge placed at the right angle, relative to the rightward horizontal? - -18° - +18° - -45° - +45° - -85° - **+85°** **Difficulty:** medium ### 4. Point charges are placed on two of the corners... Point charges are placed on two of the corners of a triangle as shown. What magnitude of force would be felt by a 1.0 µC charge placed at the right angle? - 1.4 N - 2.9 N - 3.3 N - **5.4 N** - 6.8 N **Difficulty:** medium ### 5. A charge Q1 = Q is positioned on the x axis at x =... A charge Q1 = Q is positioned on the x axis at x = a. Where should a charge Q2 = 9Q be placed to produce a net electric force of zero on a charge placed at the origin? - at x = 2a - at x = -2a - at x = 3a - **at x = -3a** - at x = 4a **Difficulty:** medium ### 6. Three-point charges are positioned on the x-axis... Three-point charges are positioned on the x-axis. If the charges and corresponding positions are -25.0 µC at x = 0.00 cm, -50.0 µC at x = 30.0 cm, and +100.0 µC at x = 80.0 cm, what is the magnitude of the electrostatic force on the -25.0 -µC charge due to the other two charges? - **89.7 N** - 160 N - 8.97 mN - 16.0 mN - 0 N **Difficulty:** medium ### 7. A particle with charge Q is placed at each of the... A particle with charge Q is placed at each of the four corners of a square 2 m on each side. The magnitude of the electrostatic force on any one of the charges is 4.41 N. The magnitude of the charge Q is - **32 µC** - 15 µC - 48 µC - 23 µC - 67 µC **Difficulty:** medium ### 8. Two-point charges are fixed in place along... Two-point charges are fixed in place along the x-axis. The first charge of 3.8 µC is located at x = -4.5 cm, while the second charge of -5.6 µC is located at x = 3.5 cm. Where on the x-axis should a third charge with charge 1 µC be placed so that it feels no electric force? - -21.4 cm - 21.4 cm - -31.2 cm - **-41.9 cm** - 41.9 cm **Difficulty:** medium ### 9. One charge is placed at each corner of an equilateral... One charge is placed at each corner of an equilateral triangle with a length of 0.25 m on each side. The first charge is 4.5 µC, the second is 3.2 µC, and the third is 2.5 µC. What is the magnitude of the electric force on the third charge due to the first two charges? - 0.602 N - 1.96 N - **2.41 N** - 3.19 N - 4.31 N **Difficulty:** medium ### 10. Find the magnitude of the net force on a 1.20 mC... Find the magnitude of the net force on a 1.20 mC charge at the origin due to a +2.40 mC charge at (3 m, 0) and a -5.70 mC charge at (0, 4 m). - 1.8 kN - 2.9 kN - 3.8 kN - **4.8 kN** - 16 kN **Difficulty:** medium ### 11. A 1 C charge is placed at the origin and a 2 C charge... A 1 C charge is placed at the origin and a 2 C charge is placed at the position (2 m, 0). At what coordinates should a -4 C charge be placed so that the net force on that charge is zero? - (-0.5 m, 0) - **(0.83 m, 0)** - (1.34 m, 0) - (2.34 m, 0) - (0.5 m, 0.83 m) **Difficulty:** medium ### 12. A 0.5 C is placed at each of the coordinates (0, 1) and... A 0.5 C is placed at each of the coordinates (0, 1) and (1, 0) and a -0.5 C is placed at the origin. What is the direction of the force on a positive charge placed at (1, 1)? - towards the origin - towards (1, 0) - towards (0, 1) - **away from the origin** - There is not enough information given to tell. **Difficulty:** medium ### 13. Find the magnitude and direction of the electrosta... Find the magnitude and direction of the electrostatic force on the electron in the figure shown. - **5.07 × 10^-26 N to the left** - 5.07 × 10^-26 N to the right - 0 N - 6.23 × 10^-26 N to the left - 6.23 × 10^-26 N to the right **Difficulty:** medium ### 14. An electrically charged sphere is placed between... An electrically charged sphere is placed between two other charged spheres on a line segment connecting the centers of the two outer spheres. If there is no net electrostatic force on the outer spheres', which of the following can be correctly said? - The outer spheres carry charges with opposite sign. - **The outer spheres carry charges with the same sign.** - The outer spheres carry charges with equal magnitude. - The central sphere is equidistant from each of the outer spheres. - None of the above choices may be said with certainty. **Difficulty:** medium ### 15. A small ball with a mass of 40 g and a charge of -... A small ball with a mass of 40 g and a charge of -0.3 µC is suspended from the ceiling on a string. The ball is suspended above an insulating floor. If a second small ball with a mass of 50 g and a charge of 0.6 µC is placed on the floor directly beneath the first ball and the tension in the string is 1.0 N, what is the distance between the first ball and the insulating floor? - 5.7 cm - **5.2 cm** - 6.4 cm - 8.3 cm - 7.0 cm **Difficulty:** medium ### 16. A small ball with a mass of 40 g and a charge of 0... A small ball with a mass of 40 g and a charge of 0.3 µC is suspended from the ceiling on a string at a height 7.0 cm above an insulating floor. If a second small ball with a mass of 50 g and a charge of 0.6 µC is placed on the floor directly beneath the first ball, what is the tension in the string? - 0.043 N - **0.062 N** - 0.33 N - 0.39 N - 0.72 N **Difficulty:** medium ### 17. A small charged ball with a mass of 40 g is suspen... A small charged ball with a mass of 40 g is suspended from the ceiling on a string at a height of 7.0 cm above an insulating floor. If a second small ball with a mass of 50 g and a charge of -0.60 µC is placed on the floor directly beneath the first ball and the tension in the string is 1.00 N, what is the charge on the ball attached to the string? - 0.72 µC - 0.30 µC - 0.96 µC - 1.3 µC - **0.55 µC** **Difficulty:** medium ### 18. A fixed +2.0 mC charge is located at the origin, a... A fixed +2.0 mC charge is located at the origin, and a fixed -5.0 mC charge is located on the positive x-axis at x = 1.0 m. What is the x-coordinate of another point on the x-axis where a +7.0 mC charge could be placed so that the net electric force on it is zero? - **-1.7 m** - -0.67 m - -0.39 m - +0.39 m - +0.67 m **Difficulty:** medium ### 19. Three point charges, = 2.40 µC, = -, and = are... Three point charges, Q1 = 2.40 μC Q2 = Q1, and Q3 = 2/3 Q1 are placed on the x-axis as shown. The respective x-coordinates of these charges are *x1 = 0.100m x2 = 0.120 m x3 = 0.300 m*. What is the electric force on Q2? - 0.324 N - 0.366 N - 0.414 N - 0.468 N - **0.528 N** - 0.597 N - 0.675 N - 0.762 N **Difficulty:** medium ### 20. An electron in a hydrogen atom experiences a Coulo... An electron in a hydrogen atom experiences a Coulomb force with magnitude 85.2 nN, as it traverses a circular orbit around the central proton. How far away is the electron from the proton? - **0.052 nm** - 52 µm - 0.35 nm - 35 µm - 27 mm **Difficulty:** medium