Physics Electricial Circuits Review

One ampere is the amount of current that exists when ____ flows by a certain point in a conductor in ____.

1 Coulomb/1 Second

A 12-Volt battery would supply ___.

1 coulomb with 12 Joules

If 6 coulombs of charge flow past point 'A' in a circuit in 4 seconds, then ____ coulombs of charge will flow past point 'A' in 8 seconds

12

When plugged into a 120-Volt outlet, a light bulb consumes 300 joules of energy over a 5 second time period. The power of the light bulb is ____ Watts.

60W (Power is simply the rate at which energy is supplied to a circuit or transformed by a circuit. In this case, the power is the energy consumed per time.)

If a third resistor (R3), identical to the other two, is added in series with the first two, then the electric potential difference (voltage drop) across each of the three individual resistors will ____.

Decrease

If a third resistor , identical to the other two, is added in parallel with the first two, then the overall resistance will ____ and the overall current will ____.

Decrease, Increase

During any single loop of charge around a parallel circuit, the charge will pass through each resistor in the circuit. T/F

False

Suppose that two identical resistors are placed in series with a 12-Volt battery. The current in the circuit is 6 amps. The resistance of each resistor is 4 ohms. T/F

False

The electric potential of a charge at a given location provides a measure of the rate at which charge flows past that point. T/F

False

The total current in a circuit increases as more and more resistors are placed in series in the circuit. T/F

False

Suppose that three identical resistors with a resistance of 3-ohms are placed in series with a 12-Volt battery. The electric potential difference across each resistor is 12 Volts. T/F

False (4v)

A battery is used to power a flashlight circuit. When the battery no longer works, it is because it has run out of charge. T/F

False (Batteries produce energy through a exothermic chemical reaction. When a battery no longer works, the ability of its chemical reaction to produce products and energy has become limited by the depletion of reaction and the build up of products; it has run of out chemical reactants.)

The overall resistance of a circuit increases as more and more resistors are placed in parallel in the circuit. T/F

False (Consider that the new resistor actually opens up a new pathway through which the charge can pass. Not all the charge goes through all the resistors. By opening a new branch in the circuit, the fraction of charge which passes through any one resistor is reduced. So less charge actually encounters a single resistor. Now it makes sense to say that more resistors leads to less overall resistance.

A 60-Watt light bulb would consume 30 Joules of electrical energy in 2 seconds. T/F

False (Energy per time, 60x2)

Power is the amount of energy used by an electrical appliance. T/F

False (It is the rate at which energy is used by an electrical appliance)

Electric potential can also be expressed in units of Joules. T/F

False (Joules/Coulomb, not just Joules)

Electric current is defined as the number of Coulombs of charge which move past a point on a circuit. T/F

False (Number of Coulombs of charge that move past a point in a given unit of time)

A kiloWatt•hour is a unit of electric power. T/F

False (Unit of Power)

If a third resistor (R3), identical to the other two, is added in series with the first two, then the overall resistance will ____ and the overall current will ____.

Increase, Decrease

The potential energy possessed per unit of charge at any given location is referred to as the electric ___.

Potential

What occurs when a rechargeable battery is recharged?

The battery, which has run out of chemical reactants, has its chemicals reformed.

Charge flowing through this circuit is most energized at ____.

The positive terminal of the battery

A 6-Volt battery would provide 12 Joules of energy to 2 Coulombs of charge as it is moved from the - to the + terminal. T/F

True

A large resistance value indicates that the charge is encountering a relatively large amount of difficulty in moving through the circuit. T/F

True

Electric current is measured in units of Amperes. T/F

True

Electric potential can be expressed in units of volts. T/F

True

Electrons are the mobile charge carriers in an electric circuit. T/F

True

Parallel circuits are characterized by the fact that there are multiple pathways by which charge can travel from the + terminal to the - terminal. T/F

True

Series circuits are characterized by the fact that there is a single pathway by which charge can travel from the + terminal to the - terminal. T/F

True

Suppose that three identical resistors with a resistance of 3-ohms are placed in parallel with a 12-Volt battery. The electric potential difference across each resistor is 12 Volts. T/F

True

The location on an electric circuit where the charge possesses the greatest amount of electric potential energy is the + terminal of the battery. T/F

True

The overall resistance of a circuit increases as more and more resistors are placed in series in the circuit. T/F

True

The resistance of a conducting wire will increase as the length of the wire is increased. T/F

True

The resistance of an electric circuit is a measure of the overall amount of hindrance to the flow of charge through the circuit. T/F

True

Charge flowing through a battery will experience a gain in electric potential. T/F

True (In the battery, a charge is moved from a location of low energy to a location of high energy. The charge would gain electric potential energy and as such, it would also gain electric potential.)

A 5-ohm resistor would allow a current of 0.5 Amperes when 2.5 Volts is impressed across it. T/F

True (V/I = R)

A battery is needed in the circuit of your flashlight so that ____.

an electric potential difference is maintained across the circuit

Voltage ____ an electrical circuit.

is expressed across