4.2

Question 1

Ohms law

Answer 1

the current through a fixed resistor is directly proportional to the potential difference across it provided physical conditions such as temp stay the same

Question 2

ohms law equation

Answer 2

V=IR

Question 3

why must temperature stay the same in experiments

Answer 3

it will lead to an increase in the resistance of the wire. This is because an increase in temp leads to an increase in the movement of metal ions which leads to an increase in collisions bet ween them and the electrons.

Question 4

resistors in series

Answer 4

for resistors in series the total resistance is the sum of all the individual resistances R total= R1+R2+R3

Question 5

resistors in parallel

Answer 5

R total = 1/R1 + 1/R2 + 1/R3

Question 6

resistance depends on

Answer 6

length of the wire - longer=more resistance, thickness of wire thinner=more resistance, temp, conductivity

Question 7

why does resistivity change with temp

Answer 7

because R does and reistivity= RA/L

Question 8

resistivity

Answer 8

the measure of how much a material opposes electron flow

Question 9

power

Answer 9

the rate of energy transfer of a device is a product of the voltage and current passing though the components P=VI 1W = 1Js^-1