31 terms

# Physics Chapter 17

#### Terms in this set (...)

Which of the following is not a characteristic of electrical potential energy?
It results from a single charge.
When a positive charge moves in the direction of the electric field, what happens to the electrical potential energy associated with the charge?
It decreases.
Two positive point charges are initially separated by a distance of 2 cm. If their separation is increased to 6 cm, the resultant electrical potential energy is equal to what factor multiplied by the initial electrical potential energy?
1/ 3
Charge buildup between the plates of a capacitor stops when
the potential difference between the plates is equal to the applied potential difference.
When comparing the net charge of a charged capacitor with the net charge of the same capacitor when it is uncharged, the net charge is
equal in both capacitors.
When a capacitor discharges,
charges move through the circuit from one plate to the other until both plates are uncharged.
A capacitor consists of two metal plates; ____ is stored on one plate, and ____ is stored on the other.
negative charge, positive charge
What effect will be produced on a capacitor if the separation between the plates is increased?
It will decrease the capacitance.
Increasing the potential difference between the plates of a capacitor will produce what effect on the capacitor?
It will increase the charge on each plate.
A parallel-plate capacitor has a capacitance of C F. If the area of the plates is doubled while the distance between the plates is halved, the new capacitance will be
4C
How is current affected if the number of charge carriers decreases?
The current decreases.
How is current affected if the time interval over which the charge passes through a given area decreases while the amount of charge remains the same?
The current increases.
When you flip a switch to turn on a light, the delay time before the light turns on is determined by
the speed of the electric field moving in the wire.
When electrons move through a metal conductor,
they move in zigzag patterns because of repeated collisions with the vibrating metal
atoms.
The energy gained by electrons as they are accelerated by an electric field is
greater than the average loss in energy due to collisions.
The a conductor that carries a current, the drift speed of an electron is
less than the average speed of the electron between collisions.
Which of the following does not affect a material's resistance?
Ohm's law
Which of the following wires would have the least resistance, assuming that all of the wires have the same cross-sectional area?
a copper wire 5 cm in length
Which of the following wires would have the greatest resistance?
an aluminum wire 10 cm in length and 3 cm in diameter
Which of the following wires would have the least resistance?
a copper wire 5 cm in length at 10°C
Which of the following wires would have the least resistance?
an aluminum wire 40 cm in diameter at 40°C
The power ratings on lightbulbs are measures of the
rate that they give off heat and light.
When compared in a given time interval with other lightbulbs connected to a 120 V circuit, a 60 W lightbulb
converts less electrical energy to heat and light than a 100 W lightbulb.
Which set of information will allow you to calculate the kilowatt•hr usage?
the resistance, the current, and the time the circuit operates
Tripling the current in a circuit with constant resistance has the effect of changing the power by what factor?
9
Which process will double the power dissipated by a resistor?
doubling the current and making the resistance half as big
If the length of the conductor were increased, predict the amount of current at 10 volts.
less current
If the temperature of the conductor is increased, predict the amount of current at 10 volts.
less current
The resistance of the conductor is approximately:
2.0Ω
Compare to a conductor of the same material with a larger cross-sectional area, the resistance of this conductor is:
greater
When an electric current flows through a simple resistor, the energy is expended as:
heat