(2.9-2.11) IV Characteristics + variable resistors

What does the line represent on an I-V graph?

the resistance

The steeper the gradient of the line…

the lower the resistance.

Describe and explain the IV graph of a wire.

IV are directly proportional to each other for a constant temperature

Describe and explain the IV graph of different resistors.

Directly proportional at constant temp.

Gradient varies depending on specific resistance

Describe and explain the IV graph of a metal filament lamp.

As temperature increases, as does resistance.

So, it begins directly proportional but begins to curve- on both quadrants.

Describe and explain the IV graph of a diode

current will only flow through one direction.

so, flat line for negative current

steep increase at about 0.7V

Detail steps to investigate the IV characteristics of a component.

Set up a circuit with:

ammeter- to measure current through

voltmeter- to measure pd across

adjustable power pack- power source

1. record the current for different voltages

2. plot the graph of the values

What is a thermistor?

A component that changes resistance depending on the temperature:

higher temp = lower resistance

What is an LDR?

light dependent resistor

as light intensity increases = lower resistance