Fall ’12 PHY 122
Homework Solutions #6
HW6: Ch. 26 P 2, 7, 10,15, 19, 27, 33, 44
Chapter 26 Problem 2
Four 1.50-V cells are connected in series to a 12-Ω lightbulb. If the
resulting current is 0.45 A, what is the internal resistance of each
cell, assuming they are identical and neglecting the resistance of the
wires?
Chapter 26 Problem 10
Three 1.70kΩ resistors can be connected together in four different
ways, making combinations of series and/or parallel circuits. What
are these four ways, and what is the net resistance in each case?
Chapter 26 Problem 15
A close inspection of an electric circuit reveals that a 480Ω resistor
was inadvertently soldered in the place where a 370Ω resistor is
needed. How can this be fixed without removing anything from the
existing circuit?
Chapter 26 Problem 19
What is the net resistance of the circuit connected to the battery in
Fig. 26–41?
Chapter 26 Problem 27
Calculate the current in the circuit of Fig. 26–45, and show that the
sum of all the voltage changes around the circuit is zero.
Chapter 26 Problem 33
Determine the magnitudes and directions of the currents through R1
and R2 in Fig. 26–51.
Chapter 26 Problem 44
In Fig. 26–58 (same as Fig. 26–17a), the total resistance is 15.0kΩ
and the battery’s emf is 24.0 V. If the time constant is measured to
be 24.0μs calculate (a) the total capacitance of the circuit and (b) the
time it takes for the voltage across the resistor to reach 16.0 V after
the switch is closed.