Chapter 12.1, Problem 12.18P

Four charges, qa, qb, qa, and qd are fixed at the corners of a square. A charge q that is free to move located at the exact center of the square. Classify the scenarios described according to the force that would be exerted on the center charge q. Assume in each case that q is a positive charge. Do not assume that the fixed charges have equal magnitudes unless the scenario defines such an equality. qa Яс q %b Force is zero Force is to the left Force is to the right Force is undetermined

Charge qi = -q is located at position (0, d). Charge q = −2q₁ is located at position (d,0). Charge q3 = located at position (2d, 2d). 5qi is y Determine the net electric field Ĕ net at the origin. Enter your expression using ij unit vector notation in terms of the given quantities, the permittivity of free space €0, and exact rational and irrational numbers. d 9₁ d TH net = 92 d d X

solve please

= = R4 R5 = 12.5 Q. A - In the circuit shown, R₁ = R₂ = R 3 voltmeter measures the potential difference across the battery. When the switch is in position 1, the voltmeter measures V₁ = 13.8 V. When the switch is in position 2, the voltmeter measures V2 = 13.4 V. What is the emf ☐ of the battery? 14.93 = What is the battery's internal resistance r? r = V CH Ω R₁₂ V S R₁ 02 2 R₁ 4 R3 R 5

Consider the arrangement of charges shown in the figure. Four charges of equal magnitude Q but varying sign are placed at the corners of a square as indicated. A positive charge q is placed in the center. What is the direction of the net force, if any, on the center charge? Indicate your answer by placing the appropriate label in the first box. Then, suppose that the charge q were to be displaced slightly from the center position. On the figure, label each box with the arrow that best indicates the direction of the net force that would act on q if it were moved to that location. Net Force Answer Bank no force ↑ +2 0 -Q -Q +Q

Don't use ai to answer I will report you answer

When an electromagnetic wave is reflected at normal incidence on a perfectly conducting surface, the electric fieldvector of the reflected wave at the reflecting surface is the negative of that of the incident wave.a) Explain why this should be so.b) Show that the superposition of the incident and reflected waves results in a standing wave.c) What is the relationship between the magnetic field vector of the incident and reflected waves at the reflectingsurface?

Suppose there are two transformers between your house and the high-voltage transmission line that distributes the power. In addition, assume your house is the only one using electric power. At a substation the primary of a step-down transformer (turns ratio = 1:23) receives the voltage from the high-voltage transmission line. Because of your usage, a current of 51.1 mA exists in the primary of the transformer. The secondary is connected to the primary of another step- down transformer (turns ratio = 1:36) somewhere near your house, perhaps up on a telephone pole. The secondary of this transformer delivers a 240-V emf to your house. How much power is your house using? Remember that the current and voltage given in this problem are rms values.

In some places, insect "zappers," with their blue lights, are a familiar sight on a summer's night. These devices use a high voltage to electrocute insects. One such device uses an ac voltage of 3970 V, which is obtained from a standard 120-V outlet by means of a transformer. If the primary coil has 27 turns, how many turns are in the secondary coil? hel lp?