Two small metallic spheres, each of mass m = 0.20 g, are suspended as pendulums by light strings from a common point as shown in Figure P15.15. The spheres are given the same electric charge, and it is found that they come to equilibrium when each string is at an angle of θ = 5.0° with the vertical. If each string has length L = 30.0 cm, what is the magnitude of the charge on each sphere?

Review Conceptual Example 11 before attempting to work this problem. Four charges with equal magnitudes of 10.4× 10-12 Care placed at the corners of a rectangle. The lengths of the sides of the rectangles are 2.56 cm and 5.03 cm. Find the magnitude of the electric field at the center of the rectangle in Figures a and b. ANA E24 E24

In this example, we will analyze the motion of an electron that is released in an electric field. The terminals of a 100 V battery are connected to two large, parallel, horizontal plates 1.0 cm apart. The resulting charges on the plates produce an electric field E in the region between the plates that is very nearly uniform and has magnitude E = 3.0×104 N/C. Suppose the lower plate has positive charge, so that the electric field is vertically upward, as shown in (Figure 1). (The thin pink arrows represent the electric field.) If an electron is released from rest at the upper plate, what is its speed just before it reaches the lower plate? How much time is required for it to reach the lower plate? The mass of an electron is mẹ = 9.11 x 10-31 kg. The thin arrows represent the uniform electric field. 1.0 cm 100 V In this example, suppose a proton (mp = 1.67 × 10-27 kg) is released from rest at the positive plate. What is its speed just before it reaches the negative plate? Express your…

A small plastic ball of mass m = 1.50 g is suspended by a string of length L = 25.0 cm in a uniform electric field of magnitude E = 1.00 x 10³ N/C as shown in the figure. If the ball is in equilibrium when the string makes an angle = 17.5° angle with the vertical as indicated, what is the net charge on the ball? 10 E=1.00 x10³ N/C L m