Flashcards in Resistance and V=IR Deck (13):

1

## Describe the relationship between the current through a resistor and the potential difference

###
The current through a resistor (at a constant temp) is directly proportional to P.D

2

## Describe the graph for different resistors (V = x-axis, I = y-axis)

### Straight, positive lines through the origin. Different slopes on different lines because different resistors have different resistances.

3

## Describe the graph for a filament lamp (V = x-axis, I = y-axis)

###
Like a sin graph from sin(-90) to sin(90)

Page 102

4

## Describe the relationship between a filament lamp (temperature) and resistance

### As the temp. of the filament increases, the resistance increases

5

## Describe current and resistance in a diode

### Current will only flow in 1 direction through a diode. The diode has a very high resistance in the opposite direction

6

## Describe the graph for a filament lamp (V = x-axis, I = y-axis)

###
Flat line of y=0 until the origin where it increases in a positive curve, steeper than exponentially

Page 102

7

## Resistance increases with [ ]

### Temperature

8

## What happens when an electrical charge flows through a resistor? (Energy)

### Some of the electrical energy is transferred to heat energy and the resistor gets hot. The heat causes the ions in the conductor to vibrate more.

9

## Why does resistance increase as temp. increases?

### The heat (of the resistor) causes the ions in the conductor to vibrate more. This makes it more difficult for the charge-carrying electrons to get through the resistor - the current can't flow as easily and the resistance increases

10

## For most resistors there's a limit to the amount of [ ]

### current that can flow

11

## More current means an...

### Increase in temperature, which means an increase i resistance, which means the current decreases again

12

## What is the formula for potential difference?

###
P.D = Current * Resistance

V = IR

Current = Amps, A

P.D = Volts, V

Resistance = Ohms, Ω

13