Electricity

Question 1

current

Answer 1

rate of flow of charge

Question 2

potential difference

Answer 2

energy transferred per unit charge

Question 3

resistance

Answer 3

A measure of how difficult it is for charge carriers to pass a component

Question 4

conventional current

Answer 4

always matches the drift of +ve charge

Question 5

Ohms law

Answer 5

Current is directly proportional to potential difference at constant temperature

Question 6

Ohmic conductor

Answer 6

components that obey ohms law

Question 7

3 factors that affect resistance

Answer 7

• length
• area
• resistivity

Question 8

how does length affect resistance?

Answer 8

The resistance of a wire is directly proportional to its length

Question 9

how does area affect resistance?

Answer 9

The resistance of a wire is inversely proportional to the cross-sectional area

Question 10

how does resistivity affect resistance?

Answer 10

greater the resistivity, the higher the resistance

Question 11

resistivity

Answer 11

a measure of how easily a material conducts electricity

Question 12

describe how tempurature affects resistance

Answer 12

• When the temperature increases, atoms in the metal gain kinetic energy, which causes them to move more.
• Therefore, electrons collide more frequently with atoms, causing them to slow down
  *causing current to decrease and resistance to increase

Question 13

application of thermistor

Answer 13

tempurature sensors

Question 14

superconductor

Answer 14

a material which below a certain temperature (critical temperature) has zero resistivity.

Question 15

applications of superconductors

Answer 15

• super-efficient wires
• super strong electromagnet

Question 16

potential divider

Answer 16

• two or more resistors in series with a voltage source
• splits potential difference

Question 17

potential divider equation

Answer 17

V1 = V + R1/(R1+R2)

Question 18

Emf

Answer 18

the amount of chemical energy the cell transfers to electric potential energy per coulomb

Question 19

what causes internal resistance in batteries?

Answer 19

electrons colliding with atoms in the battery