ELECTRICITY Flashcards
Learn the content
RESISTANCE PRACTICAL what’s the point of the practical
to find out resistance of a wire (can look at different lengths of wire, different thickness or even different temps)
RESISTANCE PRACTICAL example apparatus
- voltmeter - measures the potential difference
- ammeter - measures the current
- metre stick - measures the length of wire that the current is going through
RESISTANCE PRACTICAL results
The longer the wire, the more resistance
The thicker the wire, the less resistance
The higher the temp the more resistance
resistance equation and units
resistance (ohms) = potential difference (V) / current (A)
RESISTANCE PRACTICAL why must the power pack be kept on a low potential difference/ what are the hazards
the wire will get very hot, could burn you
RESISTANCE PRACTICAL explain how the temperature affects the resistance
as the wire gets hot, the ions inside the wire vibrate faster so there are more collisions with the electrons cannot flow as easily
RESISTANCE PRACTICAL why is it important to switch the electricity off in between each reading
to let the wire cool down, as temperature affects resistance
