Conceptual Physics-Electricity Unit-Final Test

Question 1

Current

Answer 1

Sym. I; U. Amps; USym. A

Question 2

Voltage

Answer 2

Sym. V; U Volts; USym. V

Question 3

Resistance

Answer 3

Sym. R; U. Ohms; USym. Ω

Question 4

Power

Answer 4

Sym. P; U. Watts; USym. W

Question 5

Energy

Answer 5

Sym. E; U. kilowatt hours or joules (watts per second); USym. kWh

Question 6

What is the general trend and y intercept of a graph with current on the x-axis and voltage on the y-axis?

Answer 6

positive, (`0,0)

Question 7

What is the relationship between resistance and current?

Answer 7

As resistance increases, current decreases (an inverse relationship).

Question 8

What is the relationship between voltage and current?

Answer 8

As voltage increases, so does current (a direct relationship).

Question 9

Why do we use fuses and circuit breakers?

Answer 9

to prevent electric fires

Question 10

How are fuses and circuit breakers wired into a circuit?

Answer 10

in series

Question 11

In a parallel circuit, where would you put a switch to turn off individual devices? A. on the wires connected to the generator/battery B. on the wires connected to the devices C. On the wires connecting the A and B wires

Answer 11

B

Question 12

In a parallel circuit, where would you put a switch to turn off all the devices past a point? A. on the wires connected to the generator/battery B. on the wires connected to the devices C. On the wires connecting the A and B wires

Answer 12

C

Question 13

In a parallel circuit, where would you put a switch to turn off all the devices? A. on the wires connected to the generator/battery B. on the wires connected to the devices C. On the wires connecting the A and B wires

Answer 13

A

Question 14

What do we pay for when we use electricity on our electric bill?

Answer 14

electrical energy

Question 15

How do you measure electrical energy?

Answer 15

In kWh, kilowatt hours (or joules)

Question 16

Where does a hand generator get the energy needed to produce electric energy?

Answer 16

Mechanical energy in gears, which comes from kinetic energy of your hand turning, which comes from chemical energy in the food you ate, which comes from solar energy (from the sun)

Question 17

What is the difference between a series circuit and a parallel circuit in terms of use, and how current and resistance are calculated?

Answer 17

Series circuits are used to wire in fuses and circuit breakers. Parallel circuits are used in homes and buildings.
In series, current is the same everywhere as the battery. In parallel, current is divided equally among the branches.
In series, resistance adds (goes up as you add resistance and current goes down). In parallel you add the reciprocals (1/R1+1/R2+1/R3…)? Then invert the answer? (goes down as you add resistance and current goes up).

Question 18

How does a fuse work?

Answer 18

When the current goes too fast, it melts, “breaking” the circuit.

Question 19

How does a circuit breaker work?

Answer 19

When the current goes too fast, it bends away from the other side, “breaking” the circuit.

Question 20

How is an ammeter wired into a circuit?

Answer 20

In circuit

Question 21

How is a voltmeter wired into a circuit?

Answer 21

in parallel

Question 22

If a conductor is carrying 9 A of current, and then splits into two different wires, one of which carries 4 A, what current does the other wire have?

Answer 22

5 A

Question 23

Does a line with a steeper incline have a greater or lesser resistance in a graph (x=current, y=voltage)?

Answer 23

A greater

Question 24

What is Ohm’s Law?

Answer 24

It is the equation for voltage: Voltage=current x resistance (V=IR).

Question 25

What is the equation for Power?

Answer 25

Power=current x voltage (P=IV)

Question 26

What is the equation for Energy?

Answer 26

Energy=power x time (E=Pt)

Question 27

If you are given voltage and power, what equation do you use to find what?

Answer 27

P=IV (power)

to find current

Question 28

If you are given time and power, what equation do you use to find what?

Answer 28

E=Pt (energy)

to find energy

Question 29

If you are given resistance and one other thing, what equation are you going to use?

Answer 29

V=IR (Ohm’s Law)

Question 30

IF you are given current and voltage, which equations could you be using, depending on what you are looking for?

Answer 30

To find Power: P=IV (power)

To find Resistance: V=IR (Ohm’s Law)

Question 31

What voltage does a typical household outlet have?

Answer 31

120 Volts

Question 32

When given a list of appliances with their wattages, how could you find the overall wattage?

Answer 32

Add the watts

Question 33

Energy cannot be blank or blank.

It can only blank blank.

Answer 33

Energy cannot be created or destroyed.

It can only change forms.

Question 34

A circuit is a complete blank for blank current that contains a blank device and a method to convert electrical energy to blank blank blank blank.

Answer 34

A circuit is a complete path for electrical current that contains a generating device and a method to convert electrical energy to another form of energy.

Question 35

Power is…

Answer 35

a measure of the rate at which energy is converted.

Question 36

A generator converts energy from blank to blank

Answer 36

non-electrical to electrical

Question 37

As current flow increases, power use blank

Answer 37

increases

Question 38

Ohm’s law explains the relationship between blank, blank, and blank

Answer 38

current, voltage, and resistance

Question 39

Power can be calculated as the product of blank and blank.

Answer 39

current and voltage.

Question 40

As current flows through a circuit, the amount of voltage is blank until it reaches blank at the end of its path

Answer 40

reduced

zero

Question 41

The current flowing through a circuit may separate along different paths, but the total amount of current…

Answer 41

will not change.