P3.2.3 - Resistance Flashcards
1
Q
What is resistance?
A
The opposition to the passage of charge
2
Q
How do you calculate resistance?
A
current = potential difference / resistance
3
Q
How is resistance produced in a metal?
A
Resistance is produced when delocalised electrons collides with the ions in the lattice
4
Q
What is a variable resistor?
A
A component which has a resistance you can vary by changing the amount of wire or other resisting material
5
Q
What increases the resistance?
A
- The faster the ions vibrate
- the bigger the ions
6
Q
If you increase the resistance…
A
the current decreases
7
Q
Why do thick wires have less resistance?
A
Because there is more space for electrons to go past
