Physics 2

An electron moving in the direction of the +x-axis enters a magnetic field. If the electron experiences a magnetic deflection in the -y direction, the direction of the magnetic field in this region points in the direction of the

-z-axis.

Two point charges Q 1 and Q 2 of equal magnitudes and opposite signs are positioned as shown in the figure. Which of the arrows best represents the net electric field at point P due to these two charges?

A

In the circuit shown in the figure, all the lightbulbs are identical. Which of the following is the correct ranking of the brightness of the bulbs? The figure shows the electric circuit with lightbulb A connected in parallel to a series of lightbulbs B and C. This combination is connected to a battery.

A is the brightest, and B and C have equal brightness but less than A.

When two or more capacitors are connected in parallel across a potential difference

As it moves farther and farther from Q1, its speed will keep increasing.

As more resistors are added in parallel across a constant voltage source, the power supplied by the source

Increases

An RC circuit is connected across an ideal DC voltage source through an open switch. The switch is closed at time t = 0 s. Which of the following statements regarding the circuit are correct? (There may be more than one correct choice.)

Once the capacitor is essentially fully charged, there is no appreciable current in the circuit.

The figure shows three electric charges labeled Q 1, Q 2, Q 3, and some electric field lines in the region surrounding the charges. What are the signs of the three charges? The figure shows three electric charges on the same horizontal line labeled Q 1, Q 2, Q 3, and electric field lines with arrows representing the direction of the electric field. Q 1 is to the left of Q 3, and Q 2 is between them. Lines starting at Q 1 are directed from Q 1 to infinity or to Q 2. Lines starting at Q 3 are directed from Q 3 to infinity or to Q 2.

Q 1 is positive, Q 2 is negative, Q 3 is positive.

The figure shows a steady electric current passing through a wire with a narrow region. What happens to the drift velocity of the moving charges as they go from region A to region B and then to region C? The figure shows a horizontal wire which consists of 3 regions. Wide region labeled A is to the left of wide region labeled C, and narrow region labeled B is between them. Each region has an equal arrow labeled I which is horizontal and directed to the right.

The drift velocity increases from A to B and decreases from B to C.

A light bulb is connected in the circuit shown in the figure with the switch S open. All the connecting leads have no appreciable resistance and the battery has no internal resistance. When we close the switch, which statements below accurately describe the behavior of the circuit? (There may be more than one correct choice.) The figure shows the electric circuit with resistor labeled R 3 followed by switch S parallel to the resistor labeled R 2. This combination is in series with resistor labeled R 1 and a bulb. This combination is connected to the battery of unknown emf so that the positive terminal of the battery is connected to resistor R 1.

The potential drop across R 2 will decrease The brightness of the bulb will increase.

X and Y are two uncharged metal spheres on insulating stands, and are in contact with each other. A positively charged rod R is brought close to X as shown in Figure (a). The figure shows two spheres on stands and the positively charged rod. The sphere on the left is marked X. The sphere on the right is marked Y. The spheres are in contact with each other. The rod is marked R and it is located to the left of sphere X. Sphere Y is now moved away from X, as in Figure (b). The figure shows two spheres on stands and the positively charged rod. The sphere on the left is marked X. The sphere on the right is marked Y and it is moved away from sphere X. The rod is marked R and it is located to the left of sphere X. What are the final charge states of X and Y?

X is negative and Y is positive.

Suppose you have two negative point charges. As you move them farther and farther apart, the potential energy of this system relative to infinity

decreases.

A vertical wire carries a current straight down. To the east of this wire, the magnetic field points

toward the south.

An electron is initially moving to the right when it enters a uniform electric field directed upwards. Which trajectory shown below will the electron follow? The figure shows four trajectories of the electron moving in the electric field. The electron velocity v is directed to the right and it is perpendicular to the electric field vector E, which is upward. Trajectory X is a straight line parallel to E and directed upward. Trajectory Y is a concave curve. Trajectory W is a straight line in the direction of v and directed to the right. Trajectory Z is a convex curve.

trajectory Z