Coulomb's Law A thin rod of length L, oriented in the x-direction, has charge +Q. The rod lies on the floor. The left end of the rod is touching a wall. On the floor, a small frictionless puck of mass M and charge Q is also touching the wall. The puck is a distance b from the left end of the rod. If the wall were removed, the puck would slide at an angle. But the wall constrains the puck to slide only in the y-direction. Here, the y-direction is not vertical. It's along the floor, perpendicular to the rod. a. What is the puck's acceleration, immediately after it's released? Hint: The wall constrains the puck to accelerate only in the y-direction. Therefore, you need to worry only about the y-directed forces. If you can't complete the math, that's OK; but set things up completely. Top down view Base of wall Puck b. What normal force does the wall exert on the puck when the puck is first released? Hint: The normal force, which points in the x-direction, must cancel the x-component of the electric force. C. If b is much larger than L, what is the puck's initial acceleration (to good approximation)? Could you have figured this out without solving part (a)? ட்.

Two balloons have equal and opposite charges. Balloon one has N = 1010 excess electrons. The balloons are separated by d = 2.8 m and each electron has a negative charge of e = 1.602 × 10-19 C. b. What is the magnitude of the force (in N) of balloon one on balloon two using the variables provided and the Coulomb constant k (k = 8.988 × 109 N m2/C2).

= Two small beads having positive charges 9₁ 92 = q are fixed at the opposite ends of a horizontal insulating rod of length d = 4.20 m. The bead with charge q₁ is at the origin. As shown in the figure below, a third small charged bead is free to slide on the rod. At what position x is the third bead in equilibrium? 91 + 92 + X = m 7q and

Measuring the Charge. You and your team are designing an experiment where two spherical insulating beads of diameter 0.45 cm and mass 0.15 g are strung together on a fine thread that passes through microscopic holes drilled through their centers. When hung vertically, the lower bead rests on a knot at the bottom of the thread and the upper bead rests upon the lower bead. When placed inside a vacuum chamber and exposed to X-rays (highly energetic electromagnetic radiation), the beads acquire equal, uniform distributions of positive charge on their surfaces due to the loss of electrons ejected when struck by the X-rays. During this experiment, the beads are hung vertically, and a gap forms between them as if the top bead were levitating above the lower one, presumably due to the repulsive electrostatic force between them. The gap, that is, the vertical separation between the top of the lower bead and the bottom of the upper bead, is 0.27 cm. (a) How much excess charge is on each bead?…

A uniformly charged thin ring has radius 15.0 cm and total charge 20.0 nC. An electron is placed on the ring's axis a distance 30.0 cm from the center of the ring and is constrained to stay on the axis of the ring. The electron is then released from rest. For related problemsolving tips and strategies, you may want to view a Video Tutor Solution of A ring of charge. ▶ Part A Part B Find the speed of the electron when it reaches the center of the ring. Express your answer in meters per second. VE ΑΣΦ V= Submit Provide Feedback Request Answer Constants ? m/s Next >

Three neutral metal balls A, B and Care suspended by cotton threads with B touching C. A negatively charged rod is brought close to A and C is touched with a finger. The finger is then removed under the presence of the rod. After the rod is removed, the charge on the balls will be A A: neutral B: negative C: negative OA: positive B: negative C: negative OA: positive B: negative C: positive A: neutral B: neutral C: neutral BXC OA: neutral B: positive C: positive

Three charges are placed on a horizontal line. Charges q1 = +7 nC and q2 = -3 nC are fixed in place, with q2 2.0 m to the right of q1. Charge q3=+5 nC is in equilibrium but free to slide on the line (but not off of it.) a. Find the distance between q3 and q1 and whether q3 is to the right or left of q1. b. If q3 can move along the line away from its initial location, is the equilibrium stable or unstable? How did you decide? c. If q3 were were on a vertical line instead, so it could move up and down but not horizontally, would the equilibrium be stable or unstable for that motion? How did you decide? m

In the figure, the point charges are located at the corners of an equilateral triangle 29 cm on a side. What is the direction of the force on qa in degrees above the negative x-axis with origin at qa?

O Macmillan Learning A large positively charged object with charge q. = 5.25 µC is brought near a negatively charged plastic ball suspended from a string of negligible mass. The suspended ball has a charge of q = -48.3 nC and a mass of 14.5 g. 9 What is the angle that the string makes with the vertical when the positively charged object is 22.5 cm from the suspended ball? The positively charged object is at the same height as the suspended ball. 6= 9. 90 Incorrect

A small sphere of mass m = 6.20 g and charge q₁ = 30.4 nC is attached to the end of a string and hangs vertically as in the figure. A second charge of equal mass and charge q₂ = -58.0 nC is located below the first charge a distance d = 2.00 cm below the first charge as in the figure. 91 92 (a) Find the tension in the string. N (b) If the string can withstand a maximum tension of 0.180 N, what is the smallest value d can have before the string breaks? cm