Electricity

Question 1

Can electricity be in positive and negative charges?

Answer 1

Yes

Question 2

What do positively charged objects lose?

Answer 2

Electrons

Question 3

What do negatively charged objects gain?

Answer 3

Electrons

Question 4

What does a conductor do?

Answer 4

Allows electric charge to flow through it.

Question 5

What does an insulator do?

Answer 5

Does not allow electric charge to flow

Question 6

What is current?

Answer 6

The rate of flow of electric positive charge

Question 7

Explain how current adds up in a series circuit.

Answer 7

Current is the same at all points throughout the circuit.

Question 8

Explain how current adds up in a parallel circuit.

Answer 8

The total current is the sum of the currents flowing through each branch.

Question 9

What is voltage?

Answer 9

Measure of the difference in electrical potential energy.

Question 10

What equals total supply voltage?

Answer 10

The sum of potential differences around a circuit

Question 11

What is resistance?

Answer 11

The ratio of potential difference across a component to the current through that component.

Question 12

Describe an experiment to determine resistance using an ammeter and voltmeter.

Question 13

What does resistance equal?

Answer 13

Voltage/ Current

Question 14

What is Ohm’s Law?

Answer 14

V = IR

Question 15

Calculate the combined resistance of 2 or more series resistors

Question 16

Describe the simple experiments to show the production and detection of static charge

Answer 16

Production of Static Charge by Friction, to produce static electricity by rubbing two different materials together. When you rub the comb or balloon with the wool cloth or fur, electrons are transferred from one material to the other. This transfer of electrons causes one object to become negatively charged (gains electrons) and the other to become positively charged (loses electrons). The static charge on the comb or balloon creates an electric field that induces a charge on the small pieces of paper, causing them to be attracted to the charged object.

Question 17

Explain charge differences in static electricity.

Answer 17

Static electricity is all about the imbalance of electric charges on the surface of objects. This imbalance creates an electric field that can cause various effects. Static electricity occurs when electrons are transferred from one material to another.

Question 18

Why does static electricity cause hair to stand on air?

Answer 18

When you comb your hair with a plastic comb, electrons are transferred from your hair to the comb. From this the hair becomes positively charged. From this each strand of hair has the same positive charge. Like charges repel each other so they try to move from each other and as they are rather light weight they ‘stand up’.

Question 19

Why does static electricity make balloons pick up paper?

Answer 19

When the balloon becomes statically charged it gets a negative charge from picking up electrons. The balloon’s negative charge induces a positive charge on paper closest to the balloon. This happens because the balloon’s electric field causes the electrons in the paper to move slightly away, leaving the near side of the paper with a positive charge. So as opposite charges attracts the balloon picks up the piece of paper.

Question 20

Design a circuit to distinguish between conductors and insulators.

Answer 20

battery - material- bulb - battery

Question 21

What is resistance in circuits?

Answer 21

A measure of how much a material or component opposes the flow of electric current, measured in ohms (Ω). Resistance occurs because as electrons move through a conductor. This opposition to the flow of electrons is what we call resistance. Ohm’s Law means for a given resistance, the voltage across a component is directly proportional to the current flowing through it. It is a key factor in designing and analysing electrical circuits, affecting everything from current flow to voltage.

Question 22

What is the difference between high and low resistance?

Answer 22

Higher resistance means less current will flow for a given voltage. Lower resistance= easier current flow.

Question 23

What are the 3 roles of resistance in circuits?

Answer 23

Controlling Current: By adding resistors to a circuit, you can control the amount of current that flows through different parts of the circuit.

Power Dissipation: Resistance causes electrical energy to be converted into heat. This is why resistors can get warm when current flows through them. The power dissipated as heat in a resistor is given by:
​P= I squared X R
or
P= V squared divided by R

Question 24

Describe an experiment to determine resistance using an ammeter and a voltmeter.

Answer 24

By accurately measuring the voltage across the resistor and the current flowing through it, you can determine the resistance of the resistor using Ohm’s Law.

Question 25

What is an Ohmic resistor?

Answer 25

It is a resistor that obeys Ohm’s law at all voltages or currents.

Question 26

What are the advantages of connecting lamps to a lightning circuit?

Answer 26

Consistent Voltage Across Each Lamp
Independent Operation
Even Distribution of Power
Scalability, can always add more lamps without affecting other lamps
Reliability

Question 27

What does TOTAL RESISTANCE equal?

Answer 27

R1+R2+R3=Rtotal

Question 28

What does R mean?

Answer 28

resistance measured in Ohms

Question 29

What does I mean

Answer 29

current measured in amps

Question 30

What does V mean

Answer 30

Voletage measured in Volts

Question 31

what is a coulomb

Answer 31

One coulomb is equal to the amount of charge from a current of one ampere flowing for one second

Question 32

what is charge measured in

Answer 32

coulombs