Physics Circuits Test Review

In an series circuit, the ________________ in voltage provided by the __________________ or other energy source, V source, is equal to the _______ of voltage ____________

- increase - generator - sum - drops

If a 75 W light bulb operates at a voltage of 120 V. What's the current in the bulb?

0.63 A

A light bulb uses 100 W of power, when connected across 120 V. What's the current drawn by the light bulb?

0.8 A

How do you find the total resistance in a parallel circuit?

1 / 1/R1 + 1/R2

3 resistors with values of 4 ohms, 6 ohms, and 10 ohms are connected in parallel. What is their equivalent resistance?

1.9 ohms

A 2 ohms and 12 ohms resistor are connected in a parallel across a 20 V battery. What is the current through the 2 ohm resistor?

10 A

2 resistors of 5 ohms and 7 ohms are connected in series across a 24 V battery. What's the voltage drop across each resistance?

10 V across the 5 ohms resistor, 14 V across the 7 ohms resistor

A 20 ohms and 40 ohms resistor are connected in series across a battery. If the current is 2 A, what's the voltage of the battery?

120 V

3 resistors with values of 4 ohms, 6 ohms, and 8 ohms, are connected in series. What's their equivalent resistance?

18

A 2.0 ohm resistor and a 4.0 ohm resistor are connected in series with a 12V battery. If the current through the 2.0 ohm resistor is 2.0 Amps, the current through the 4.0 ohm resistor is...

2 A

3 resistors 4 ohms, 8 ohms, and 10 ohms are connected in series across an 11 V battery. The total potential difference across the 4 ohms resistor is:

2 V

In a simple circuit, a voltage of 5 V is applied across a resistance of 10 ohms. What's the power dissipated in the resistor?

2.5 W

In a series circuit, 3 loads have a potential difference of 8 V, 12 V, and 3.4 . The total current in the circuit is 3 A. What's the amount of current through the 2nd load?

3 A

In the circuit shown R1 = 20 ohms, R2 = 10 ohms, and the battery is 60 Volts. What is the voltage drop across the 20 ohm resistor? (series circuit)

40 V

3 resistors of 10 ohms, 20 ohms, and 25 ohms are connected in a parallel across a 100 V battery. What's the equivalent resistance of the circuit and the current flowing through the 10 ohms resistor?

5.26 ohms and 10 A

If a 325 W heater has a current of 6 A, what's the resistance of the heating element?

9 ohms

Which bulb has the most voltage across it?

All bulbs have the same voltage

What happens if bulb A is unscrewed? (parallel circuit and bulb B's on the same line)

Bulb B will go out

Which bulb has the most current flowing through it? (parallel circuit and Bulb A, B, and C are all on different wires)

Bulb C

What happens if bulb C is unscrewed? (parallel circuit and Bulb C is on the wire closest to the battery and Bulb B and C are on the wire farthest from the battery)

Bulbs A and B will stay lit

How do you find voltage?

Current x Resistance

How do you find power?

Current x Voltage

How can you decrease the amount of resistance in a wire?

Decrease the length

As the # of resistors in a parallel circuit is increased, what happens to the equivalent resistance of the circuit and total current in the circuit?

Equivalent resistance decreases and the total current increases

A parallel connection is a type of electrical circuit in which there's a single current pathway (T or F)

False

A series connection is a type of electric circuit in which there are multiple paths (T or F)

False

In an electric circuit, charges:

Flow around in a closed loop, get energy from an external source, and flow from higher potential to lower potential

What's the effect on the current in a simple circuit when BOTH the voltage and the resistance are multiplied by 2?

I

How do you find the total current in a parallel circuit?

I1 + I2 + I3 (add all of the currents together)

According to Ohm's Law, if the voltage is increased, what happens to the current across the resistor?

It increases

As loads are added in parallel to a circuit, what happens to the total current in the circuit?

It increases

When 1 bulb in a series circuit containing several light bulbs burns out:

None of the other bulbs will light up

Series or parallel circuit? Type of circuit used to wire buildings

Parallel circuit

Series or parallel circuit? Voltage throughout the circuit remains the same

Parallel circuit

Series or parallel circuit? When 1 light bulb burns out, the rest will stay lit

Parallel circuit

The rate at which electric energy is transferred is:

Power

How do you find the total resistance in a series circuit?

R1 + R2 + R3 = Total resistance

Series circuit or Parallel circuit When 1 light bulb turns out, they all go out.

Series circuit

Series or parallel circuit? Current remains the same throughout the entire circuit

Series circuit

Series or parallel circuit? The total potential difference is the sum of all the voltage drops

Series circuit

When resistors are put in parallel with each other their overall resistance is:

Smaller than resistance of any of the resistors

3 resistors connected in series carry currents labeled 1,2,3. Which of the following expresses the total current in the system made up of the 3 resistors in series?

Total current = Current #1 = Current #2 = Current #3

A resistor is a device that controls current in electric circuits (T or F)

True

How do you find the voltage of a battery in a series circuit?

Voltage of R1 + Voltage of R2

If a branch with a resistor is added to a parallel circuit, the equivalent resistance:

decreases

The current flowing in an electric circuit can be increased by:

increasing voltage or decreasing resistance

In a series circuit the __________ current goes through all the resistors

same

The voltage in a parallel circuit is the __________ across each path

same

A/An ____________ _______________ is described as a type of circuit in which there's only a single current path

series circuit