1. 5.3 More current – pd graphs The resistance of a filament lamp increases with increased temperature The resistance of a diode depends on the p.d. (voltage) applied. The resistance of a thermistor decreases as temperature increases. As light increases the resistance of an LDR decreases. 05 June 2016

2. Voltage current graphs I V I V I V I V 1 2 34 For each graph describe what happens when the potential difference (V) is increased. Use terms such as, directly proportional, rate of increase, rate of decrease, high gradient, low gradient.

3. Filament Lamp A filament is a thin strip of wire made very hot (2000ºC) by electric current running through it. This makes it white hot! This is the graph for a filament bulb. How does the resistance change when the bulb gets hotter? Using the idea of atoms can you explain why?

4. Thermistor A semi conductor which changes its resistance when temperature changes. Higher temperatures means a lower resistance. What does this graph show about the resistance of a thermistor?

5. Light Dependent Resistor (LDR) A piece of semi conductor which changes its resistance with light level.