Resistance

Question 1

A material with many free electrons will pass current freely is called a?

Answer 1

Conductor

Question 2

List examples of a conductor.

Answer 2

1. Aluminium
2. Copper
3. Gold
4. Silver
5. Platinum
6. Mercury

Question 3

What is a material with few free electrons and will only pass current with difficulty is called?

Answer 3

An insulator

Question 4

List examples of an Insulator.

Answer 4

1. Plastic
2. Wood
3. Mica
4. Rubber
5. Paper
6. Glass
7. Sea Water

Question 5

What different factors which affect the resistance of a conductor?

Answer 5

1. Type of material
2. Length of conductor (Double the length double the resistance, Halve length halve resistance)
3. Cross sectional area of conductor (Thicker lower resistance, Thinner higher resistance)
4. Temperature (Hotter higher , Colder lower)

Question 6

Ohm’s law states that a _____ flowing through a conductor

Answer 6

Current

Question 7

is directly proportional to the applied _____ across it,

Answer 7

Voltage

Question 8

providing the _____ remains constant

Answer 8

Temperature

Question 9

and is _____ proportional to the resistance.

Answer 9

Inversley

Question 10

What is the unit of resistance?

Answer 10

Ohms (Ω)

Question 11

State the formula for calculating total resistance in a series circuit.

Answer 11

Rt = R1+R2+R3

Question 12

State the formula for calculating total resistance in a parallel circuit.

Answer 12

1/Rt = 1/R1 + 1/R2 + 1/R3

Question 13

After working out total resistance (Rt) in a parallel circuit, what is a good check that your answer is correct?

Answer 13

Rt should have a lower value than the lowest resistor.

Question 14

State the Ohms law triangle

Answer 14

V = I xR