Three equal charges are at three of the corners of a square of side d. A fourth charge of equal magnitude is at the center of the square as shown in Figure above. Which of the arrows shown represents the net force acting on the charge at the center of the square?

Which of the following expressions gives the capacitance for a capacitor in a circuit in which the only factors known are a) the current through the circuit, b) the resistance of the circuit, and c) the charge that has accumulated on the capacitor?

What is the RMS voltage of a peak-to-peak AC current?

You are given three resistors with known values:

You are asked to create a circuit with a total resistance of between and . How should you arrange the resistors to accomplish this?

What size resistor should be connected across the terminals of a battery to produce a current of ?

For most people, the nearest distance that objects can be located away from the eye and still seen clearly is . This is referred to as the near point; if the object comes any closer, the object cannot be seen clearly. Suppose that a person who needs glasses cannot see objects clearly if they are closer than from the eye; that is to say, their near point is . A lens with what refractive power is needed in order to correct this person's vision to bring their near point to ?

A light ray is traveling through air hits a transparent material at an angle of from the normal. It is then refracted at . What is the speed of light in the material?

What size resistor should be connected across the terminals of a battery to produce a current of ?

Suppose that a magnetic field is oriented such that it is pointing directly to the left, as in the picture shown below. If a positively charged particle were to begin traveling through this magnetic field to the right, in which direction would the particle's trajectory begin to curve?

Suppose that car A and car B are both traveling in the same direction. Car A is going and is sounding a horn with a frequency of . If car B is traveling at a speed of in front of car A, what frequency of sound does car B hear?

Note: The speed of sound in air is .