Flashcards in Conceptual Physics-Electricity Unit-Final Test Deck (41):

1

## Current

### Sym. I; U. Amps; USym. A

2

## Voltage

### Sym. V; U Volts; USym. V

3

## Resistance

### Sym. R; U. Ohms; USym. Ω

4

## Power

### Sym. P; U. Watts; USym. W

5

## Energy

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

6

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

### positive, (`0,0)

7

## What is the relationship between resistance and current?

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

8

## What is the relationship between voltage and current?

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

9

## Why do we use fuses and circuit breakers?

### to prevent electric fires

10

## How are fuses and circuit breakers wired into a circuit?

### in series

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

### B

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

### C

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

### A

14

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

### electrical energy

15

## How do you measure electrical energy?

### In kWh, kilowatt hours (or joules)

16

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

### 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)

17

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

###
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).

18

## How does a fuse work?

### When the current goes too fast, it melts, "breaking" the circuit.

19

## How does a circuit breaker work?

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

20

## How is an ammeter wired into a circuit?

### In circuit

21

## How is a voltmeter wired into a circuit?

### in parallel

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?

### 5 A

23

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

### A greater

24

## What is Ohm's Law?

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

25

## What is the equation for Power?

### Power=current x voltage (P=IV)

26

## What is the equation for Energy?

### Energy=power x time (E=Pt)

27

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

###
P=IV (power)

to find current

28

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

###
E=Pt (energy)

to find energy

29

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

### V=IR (Ohm's Law)

30

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

###
To find Power: P=IV (power)

To find Resistance: V=IR (Ohm's Law)

31

## What voltage does a typical household outlet have?

### 120 Volts

32

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

### Add the watts

33

##
Energy cannot be blank or blank.

It can only blank blank.

###
Energy cannot be created or destroyed.

It can only change forms.

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.

### 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.

35

## Power is...

### a measure of the rate at which energy is converted.

36

## A generator converts energy from blank to blank

### non-electrical to electrical

37

## As current flow increases, power use blank

### increases

38

## Ohm's law explains the relationship between blank, blank, and blank

### current, voltage, and resistance

39

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

### current and voltage.

40

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

###
reduced

zero

41