Resistance

Question 1

What does resistance determine?

Answer 1

the amount of current we get for a particular pd

Question 2

What is resistance?

Answer 2

A measure of how difficult it is for current to flow

Question 3

What is the equation for resistance?

Answer 3

R = V/I 
r = resistance 
v = pd 
i = current

Question 4

How does resistance behave in series?

Answer 4

work with each other

Rt = R1 + R2 ………

Question 5

How does resistance behave in parallel?

Answer 5

Work against each other

1/Rt = 1/R1 + 1/R2………………

Question 6

What is resistance caused by?

Answer 6

It is caused by the vibration of the ions within the lattice causing collisions with charge carriers. Vibrations increase with temperature.

Question 7

What are the factors affecting resistance?

Answer 7

• length
• area
• resistivity

Question 8

How does length affect resistance

Answer 8

increases it, as the longer the wire the more collisions can happen

Question 9

How does area affect the resistance?

Answer 9

decreases the resistance , as the wider the wire the easier it is for charge carriers to flow, so greater I (rate of flow of charge)

Question 10

How does resistivity affect resistance?

Answer 10

can go both ways, it depends upon the structure

Question 11

What are the 2 types of resistors?

Answer 11

a fixed one and a variable one