1
Cambridge IGCSE
Physics
Revision Guide 2024
Unit 4 Part 1 Electricity
Mohammed Ali
[Physics with Mo Ali]
Cambridge IGCSE Physics Revision Guide by Mo Ali – Unit 4 – Part 1
, 2
Static Electricity
1 State that there are positive and negative charges
2 State that positive charges repel other positive charges, negative charges repel other negative charges, but positive
charges attract negative charges
3 Describe simple experiments to show the production of electrostatic charges by friction and to show the detection of
electrostatic charges
4 Explain that charging of solids by friction involves only a transfer of negative charge (electrons)
5 Describe an experiment to distinguish between electrical conductors and insulators
6 Recall and use a simple electron model to explain the difference between electrical conductors and insulators and
give typical examples
7 State that charge is measured in coulombs
8 Describe an electric field as a region in which an electric charge experiences a force
9 State that the direction of an electric field at a point is the direction of the force on a positive charge at that point
10 Describe simple electric field patterns, including the direction of the field:
a. around a point charge
b. around a charged conducting sphere
c. between two oppositely charged parallel conducting plates (end effects will not be examined)
Define Electric Charge: property of matter that experiences a force near other charges (Coulomb, C)
There are positive and negative charges.
Like charges repel, opposite charges attract. Neutral and charges attract. Neutral and neutral experience no force.
Electrical conductors: conduct electricity because they have free moving electrons (copper, iron, aluminium, all
metals).
Electrical insulators: cannot conduct electricity because they do no have free moving electrons (rubber, plastic, glass,
wood, etc..)
Insulators can be statically charged by rubbing. The friction causes electrons to be transferred from one insulator to the
other. The object that loses electrons becomes positive, and the one that gains electrons is negative.
*This can be tested by bringing the charged object next to another charged object (it will attract or repel) or near
neutral objects (it will attract).
Cambridge IGCSE Physics Revision Guide by Mo Ali – Unit 4 – Part 1
, 3
Define Electric Field: Region where electric charges experience a force.
Define Electric Field Direction: force on a positive charge at that point. Field lines are always drawn from positive to
negative.
*Note: As the space between field lines decreases, the strength of the field increases.
From June 2023 Paper 42 Question 8
Cambridge IGCSE Physics Revision Guide by Mo Ali – Unit 4 – Part 1
Cambridge IGCSE
Physics
Revision Guide 2024
Unit 4 Part 1 Electricity
Mohammed Ali
[Physics with Mo Ali]
Cambridge IGCSE Physics Revision Guide by Mo Ali – Unit 4 – Part 1
, 2
Static Electricity
1 State that there are positive and negative charges
2 State that positive charges repel other positive charges, negative charges repel other negative charges, but positive
charges attract negative charges
3 Describe simple experiments to show the production of electrostatic charges by friction and to show the detection of
electrostatic charges
4 Explain that charging of solids by friction involves only a transfer of negative charge (electrons)
5 Describe an experiment to distinguish between electrical conductors and insulators
6 Recall and use a simple electron model to explain the difference between electrical conductors and insulators and
give typical examples
7 State that charge is measured in coulombs
8 Describe an electric field as a region in which an electric charge experiences a force
9 State that the direction of an electric field at a point is the direction of the force on a positive charge at that point
10 Describe simple electric field patterns, including the direction of the field:
a. around a point charge
b. around a charged conducting sphere
c. between two oppositely charged parallel conducting plates (end effects will not be examined)
Define Electric Charge: property of matter that experiences a force near other charges (Coulomb, C)
There are positive and negative charges.
Like charges repel, opposite charges attract. Neutral and charges attract. Neutral and neutral experience no force.
Electrical conductors: conduct electricity because they have free moving electrons (copper, iron, aluminium, all
metals).
Electrical insulators: cannot conduct electricity because they do no have free moving electrons (rubber, plastic, glass,
wood, etc..)
Insulators can be statically charged by rubbing. The friction causes electrons to be transferred from one insulator to the
other. The object that loses electrons becomes positive, and the one that gains electrons is negative.
*This can be tested by bringing the charged object next to another charged object (it will attract or repel) or near
neutral objects (it will attract).
Cambridge IGCSE Physics Revision Guide by Mo Ali – Unit 4 – Part 1
, 3
Define Electric Field: Region where electric charges experience a force.
Define Electric Field Direction: force on a positive charge at that point. Field lines are always drawn from positive to
negative.
*Note: As the space between field lines decreases, the strength of the field increases.
From June 2023 Paper 42 Question 8
Cambridge IGCSE Physics Revision Guide by Mo Ali – Unit 4 – Part 1
