Ch 19 Mastering

Which resistor shown in (Figure 1) has the greatest current going through it? Assume that all the resistors are equal. R3 and R4. R5. R1 and R2. R1. All the resistors have the same current going through them.

What happens to the brightness of bulb A if you replace bulb B with a short circuit?

For the circuit shown in (Figure 1) , what happens when the switch S is closed? The capacitor immediately charges up to the battery emf. The capacitor charges up to a fraction of the battery emf determined by R only. Nothing. Current cannot flow through the capacitor. The capacitor eventually charges up to the full battery emf at a rate determined by R and C. The capacitor charges up to a fraction of the battery emf determined by R and C.

Describe the effective capacitance when capacitors are connected in series and in parallel.

The junction rule describes the conservation of which quantity? Note that this rule applies only to circuits that are in a steady state.

Apply the junction rule to the junction labeled with the number 1 (at the bottom of the resistor of resistance R2). Apply the loop rule to loop 2 (the smaller loop on the right). Sum the voltage changes across each circuit element around this loop going in the direction of the arrow. Remember that the current meter is ideal. Now apply the loop rule to loop 1 (the larger loop spanning the entire circuit). Sum the voltage changes across each circuit element around this loop going in the direction of the arrow.

An ammeter is connected in series to a battery of voltage Vb and a resistor of unknown resistance Ru (Figure 1) . The ammeter reads a current I0. Next, a resistor of unknown resistance Rr is connected in series to the ammeter, and the ammeter's reading drops to I1. Finally, a second resistor, also of resistance Rr, is connected in series as well. Now the ammeter reads I2.

What are the charges on plates 3 and 6? If the voltage across the first capacitor (the one with capacitance C) is ?V1, then what are the voltages across the second and third capacitors? Find the voltage ?V1 across the first capacitor. Find the charge Q on the first capacitor. Using the value of Q just calculated, find the equivalent capacitance Ceq for this combination of capacitors in series.

In the diagram below,(Figure 1) the two resistors, R1 and R2, are identical and the capacitor is initially uncharged with the switch open. How does the current through R1 compare with the current through R2 immediately after the switch is first closed? How does the current through R1 compare with the current through R2 a very long time after the switch has been closed? How does the current through R1 compare with the current through R2 immediately after the switch is opened (after being closed a very long time)?

If the potential of plate 1 is V, then, in equilibrium, what are the potentials of plates 3 and 6? Assume that the negative terminal of the battery is at zero potential.

If the charge of the first capacitor (the one with capacitance C) is Q, then what are the charges of the second and third capacitors?

Suppose we consider the system of the three capacitors as a single "equivalent" capacitor. Given the charges of the three individual capacitors calculated in the previous part, find the total charge Qtot for this equivalent capacitor.