Electricity and Energy

Question 1

What are the two types of Electrical Charge?

Answer 1

Positive and Negative

Question 2

What do like charges do?

Answer 2

Repel
(Positive Repels Positive)
(Negative Repels Negative)

Question 3

What do opposite charges do?

Answer 3

Attract
(Negative attracts Positive)
(Positive attracts Negative)

Question 4

Describe the model of an atom?

Answer 4

Contains Protons which have a positive charge, neutrons which have no charge and electrons which have a negative charge.

Question 5

How do we charge materials?

Answer 5

Giving the material electrons which will make it negatively charged or by removing electrons to make it positively charged.

Question 6

Electrons are the only thing that can do what?

Answer 6

Move

Question 7

What is an electric current?

Answer 7

An electric current is a flow of negatively charged electrons.
An electric current flows from negative to positive

Question 8

What is electric charge measured in?

Answer 8

Coulombs, C

Question 9

Describe Ohms Law?

Answer 9

Voltage = Current x Resistance

V=IR

Question 10

What do you call an opponent that obeys ohms law?

Answer 10

An ohmic component

Question 11

As the voltage across a bulb increases, what happens to the current?

Answer 11

Current also increases

Question 12

How can the resistance of a wire be altered?

Answer 12

Changing length, material or thickness?

Question 13

Describe the difference in resistance when the wires factors are changed?

Answer 13

A long wire has a greater resistance than a short wire

A thick wire has a lower resistance than a thin wire

Question 14

How do we calculate the total resistance in a series circuit?

Answer 14

RT= R1 + R2 = R3

Question 15

How do we calculate the total resistance in a parallel circuit?

Answer 15

1/RT = 1/R1 + 1/R2

Question 16

What is voltage?

Answer 16

The voltage is the energy provided for every coulomb of charge

Question 17

What can voltage also be measured in?

Answer 17

Joules per Coulomb

Question 18

What is the definition of the volt?

Answer 18

If 1 joule of work is done in moving 1 coulomb of charge between 2 points, the potential difference between the 2 points is 1 volt

Question 19

What are some of the uses for Electrostatics?

Answer 19

Making photocopies
removing dirt from air
spraying car bodies
Spraying crops
cling film

Question 20

Describe the terms insulators and conductors?

Answer 20

Insulators do not allow an electric current to flow through them
Conductors allow an electric current to flow through them

Question 21

Explain Direct Current?

Answer 21

Direct Current flows from the negative side of the power supply to the positive side.
Batteries and cells provide a direct current

Question 22

Explain Alternating Current?

Answer 22

An alternating current flows from one side of the power supply for a short period of time then travels to the other for a short period of time.
(Alternates Direction)
Mains supply provides an alternating current

Question 23

What is the frequency of mains supply?

Answer 23

50Hz

Question 24

What is mains voltage and mains peak voltage is?

Answer 24

230V

325V

Question 25

A big resistance means what in relation to voltage?

Answer 25

Bigger share of the voltage?

Question 26

When the temperature increases what happens to the resistance of the thermistor?

Answer 26

Resistance of thermistor decreases

Question 27

When the light intensity increase what happens to the resistance of the L.D.R?

Answer 27

Resistance of L.D.R Decreases

Question 28

What Equation links power, current and voltage?

Answer 28

P=IV

Question 29

What does the power rating of an appliance tell us?

Answer 29

The rate at which electrical energy is used

Question 30

What is the job of a fuse?

Answer 30

To protect the component from a large current?

Question 31

What fuse is used when the power is less than 720W?

Answer 31

3A Fuse

Question 32

What fuse is used when the power is greater than 720W?

Answer 32

13A Fuse

Question 33

What are the forms of energy?

Answer 33

Heat, Light, Sound, Electrical, Kinetic, Potential, Nuclear and Chemical

Question 34

What is special about energy?

Answer 34

Energy cannot be created or destroyed only changed from one source to another.

Question 35

What does specific heat capacity men?

Answer 35

The specific heat capacity of a material tells us the energy required to raise the temperature of 1kg of that substance by 1 Degrees Celsius

Question 36

What does latent heat mean?

Answer 36

Latent heat is the energy required to change the state of 1kg of a substance

Question 37

There is no change in what when a substance changes what?

Answer 37

There is no change in TEMPERATURE when a substance changes STATE

Question 38

What is known as the Kinetic theory?

Answer 38

The atomic model of a gas

Question 39

What is pressure?

Answer 39

Pressure is the force per unit area

Question 40

when volume decreases what happens to the pressure?

Answer 40

Pressure increases when volume decreases

Question 41

When volume is halved what happens to the pressure?

Answer 41

Pressure doubles when volume is halved.

Question 42

0 degrees Celsius is what in kelvin?

Answer 42

273 Kelvin