Electric Fields:
Coulomb’s Law of Electrostatics:
Direction of Electric Field Lines:
Statement of Coulomb’s Law:
• Gravitational field lines around Earth are directed
• Coulomb’s law = The force of attraction or towards Earth due to the direction of force exerted
repulsion between 2 electric charges at rest is on a mass in the field.
directly proportional to the product of the • The positively charged sphere attracts the negative
charges and inversely proportional to the test charge and repels the positive test charge.
square of the distance between their centres.
𝑄 𝑄
• Lines are further apart when they’re further from
• 𝐹 ∝ 𝑟1 2 2 . U1: the sphere – field gets weaker and so does the force
𝑄 𝑄
• F = k 𝑟1 2 2 . Electrostatics on a charge.
• SI units: • Electric field = region of space where an electric
(A)
Sample
- Newtons (N) for force.
- Coulombs (C) for charge.
- Metres (m) for distance.
charge experiences a force.
• Electric field line = shows the direction of force
experienced by a small positive charge placed in the
field.
Summaries after sampleConservation &
Quantisation of Charge:
• Law of conservation of electrical charge = charge
can’t be created or destroyed.
Q +Q
• Q = 12 2 . Superposition of Forces:
• Principle of quantisation of electric charge = charge
is found as a multiple of the charge (qe) on an • Q1 and Q2 will each exert a force on q if it is in their
electron. electric field – forces are superposed.
• How to calculate the resultant of superposed
forces:
- Step 1: Use Coulomb’s equation to calculate
the force between each pair of charges.
- Step 2: Draw free body diagram showing the
magnitudes and directions of the 2 forces on q.
- Step 3: Use vector addition to calculate the
resultant force.
-
GR11 PS T3-C6 •
Mind Map Via Afrika Copyright © www.summariessa.co.za (DO NOT COPY)
,Sample
Summaries after sample
,Sample
Summaries after sample
,Sample
Summaries after sample
, Electric Fields:
Coulomb’s Law of Electrostatics:
Direction of Electric Field Lines:
Statement of Coulomb’s Law:
• Gravitational field lines around Earth are directed
• Coulomb’s law = The force of attraction or towards Earth due to the direction of force exerted
repulsion between 2 electric charges at rest is on a mass in the field.
directly proportional to the product of the • The positively charged sphere attracts the negative
charges and inversely proportional to the test charge and repels the positive test charge.
square of the distance between their centres.
𝑄 𝑄
• Lines are further apart when they’re further from
• 𝐹 ∝ 𝑟1 2 2 . U1: the sphere – field gets weaker and so does the force
𝑄 𝑄
• F = k 𝑟1 2 2 . Electrostatics on a charge.
• SI units: • Electric field = region of space where an electric
(A) charge experiences a force.
- Newtons (N) for force.
- Coulombs (C) for charge. • Electric field line = shows the direction of force
- Metres (m) for distance. experienced by a small positive charge placed in the
field.
Conservation &
Quantisation of Charge:
• Law of conservation of electrical charge = charge
can’t be created or destroyed.
Q +Q
• Q = 12 2 . Superposition of Forces:
• Principle of quantisation of electric charge = charge
is found as a multiple of the charge (qe) on an • Q1 and Q2 will each exert a force on q if it is in their
electron. electric field – forces are superposed.
• How to calculate the resultant of superposed
forces:
- Step 1: Use Coulomb’s equation to calculate
the force between each pair of charges.
- Step 2: Draw free body diagram showing the
magnitudes and directions of the 2 forces on q.
- Step 3: Use vector addition to calculate the
resultant force.
-
GR11 PS T3-C6 •
Mind Map Via Afrika Copyright © www.summariessa.co.za (DO NOT COPY)
, U2: Electromagnetism:
U1: Electrostatics:
Magnetic Fields Associated
Electric Fields:
with Current-Carrying Wires:
Properties of Electric Field Lines:
Revision of Magnetic Fields &
• Directed away from the positive charge and U1: Electrostatics (B)
towards the negative charge. Field Lines:
• Evenly spaced lines represent a uniform U2:
• Compass = magnet that can turn freely at its
electric field. Electromagnetism (A) centre.
• Charges placed at any point experience the • Like poles repel and unlike poles attract.
same force. • Magnetic field = region where a magnet or a
• The lines can't cross each other. magnetic substance experiences a force.
• Magnetic field lines show the pattern and
direction of a magnetic field.
Magnitude of an Electric Field: • Electromagnets: Magnetic Field Near a Current-
- Electromagnet = combination of an
• Force is proportional to the charge.
iron core with an insulated current-
Carrying Wire:
𝐹
• E=𝑄. carrying wire around it. • Right-hand rule:
• Magnitude (E) of electric field at a point = - When an iron object is in a magnetic - Imagine holding the conductor.
the force experienced per unit charge field of a strong magnet - the iron - Your thumb points in the direction of current.
placed at the point – measured in object becomes a magnet too - - Your other fingers are curled in the direction of the
newtons per coulomb (N.C-1). referred to as an induced magnet. magnetic field.
• Electric field at a point is given by: - The south pole of an induced magnet • Current-carrying solenoid:
𝑄
E = k𝑟 2 . is closest to the north pole of the - The magnetic field is directed from north to south outside
magnet – the magnet will attract the the solenoid.
induced magnet. - The magnetic field is directed south to north inside the
- Hard magnetic substances – require solenoid.
strong magnetic fields to be - If the direction of current is reversed, polarity is reversed.
magnetised – retain their magnetism. - Right-hand solenoid rule = imagine holding a solenoid in
- Soft magnetic substances – easily your right hand – fingers curled in the direction of the
magnetised but lose their magnetism current, and your thumb points in the direction of the
immediately after being removed from magnetic field inside the solenoid.
the magnetic field. - Increasing the current and the no. of turns in the coil
increases the magnetic field.
GR11 PS T3-C6 Mind Map Via Afrika Copyright © www.summariessa.co.za (DO NOT COPY)
Coulomb’s Law of Electrostatics:
Direction of Electric Field Lines:
Statement of Coulomb’s Law:
• Gravitational field lines around Earth are directed
• Coulomb’s law = The force of attraction or towards Earth due to the direction of force exerted
repulsion between 2 electric charges at rest is on a mass in the field.
directly proportional to the product of the • The positively charged sphere attracts the negative
charges and inversely proportional to the test charge and repels the positive test charge.
square of the distance between their centres.
𝑄 𝑄
• Lines are further apart when they’re further from
• 𝐹 ∝ 𝑟1 2 2 . U1: the sphere – field gets weaker and so does the force
𝑄 𝑄
• F = k 𝑟1 2 2 . Electrostatics on a charge.
• SI units: • Electric field = region of space where an electric
(A)
Sample
- Newtons (N) for force.
- Coulombs (C) for charge.
- Metres (m) for distance.
charge experiences a force.
• Electric field line = shows the direction of force
experienced by a small positive charge placed in the
field.
Summaries after sampleConservation &
Quantisation of Charge:
• Law of conservation of electrical charge = charge
can’t be created or destroyed.
Q +Q
• Q = 12 2 . Superposition of Forces:
• Principle of quantisation of electric charge = charge
is found as a multiple of the charge (qe) on an • Q1 and Q2 will each exert a force on q if it is in their
electron. electric field – forces are superposed.
• How to calculate the resultant of superposed
forces:
- Step 1: Use Coulomb’s equation to calculate
the force between each pair of charges.
- Step 2: Draw free body diagram showing the
magnitudes and directions of the 2 forces on q.
- Step 3: Use vector addition to calculate the
resultant force.
-
GR11 PS T3-C6 •
Mind Map Via Afrika Copyright © www.summariessa.co.za (DO NOT COPY)
,Sample
Summaries after sample
,Sample
Summaries after sample
,Sample
Summaries after sample
, Electric Fields:
Coulomb’s Law of Electrostatics:
Direction of Electric Field Lines:
Statement of Coulomb’s Law:
• Gravitational field lines around Earth are directed
• Coulomb’s law = The force of attraction or towards Earth due to the direction of force exerted
repulsion between 2 electric charges at rest is on a mass in the field.
directly proportional to the product of the • The positively charged sphere attracts the negative
charges and inversely proportional to the test charge and repels the positive test charge.
square of the distance between their centres.
𝑄 𝑄
• Lines are further apart when they’re further from
• 𝐹 ∝ 𝑟1 2 2 . U1: the sphere – field gets weaker and so does the force
𝑄 𝑄
• F = k 𝑟1 2 2 . Electrostatics on a charge.
• SI units: • Electric field = region of space where an electric
(A) charge experiences a force.
- Newtons (N) for force.
- Coulombs (C) for charge. • Electric field line = shows the direction of force
- Metres (m) for distance. experienced by a small positive charge placed in the
field.
Conservation &
Quantisation of Charge:
• Law of conservation of electrical charge = charge
can’t be created or destroyed.
Q +Q
• Q = 12 2 . Superposition of Forces:
• Principle of quantisation of electric charge = charge
is found as a multiple of the charge (qe) on an • Q1 and Q2 will each exert a force on q if it is in their
electron. electric field – forces are superposed.
• How to calculate the resultant of superposed
forces:
- Step 1: Use Coulomb’s equation to calculate
the force between each pair of charges.
- Step 2: Draw free body diagram showing the
magnitudes and directions of the 2 forces on q.
- Step 3: Use vector addition to calculate the
resultant force.
-
GR11 PS T3-C6 •
Mind Map Via Afrika Copyright © www.summariessa.co.za (DO NOT COPY)
, U2: Electromagnetism:
U1: Electrostatics:
Magnetic Fields Associated
Electric Fields:
with Current-Carrying Wires:
Properties of Electric Field Lines:
Revision of Magnetic Fields &
• Directed away from the positive charge and U1: Electrostatics (B)
towards the negative charge. Field Lines:
• Evenly spaced lines represent a uniform U2:
• Compass = magnet that can turn freely at its
electric field. Electromagnetism (A) centre.
• Charges placed at any point experience the • Like poles repel and unlike poles attract.
same force. • Magnetic field = region where a magnet or a
• The lines can't cross each other. magnetic substance experiences a force.
• Magnetic field lines show the pattern and
direction of a magnetic field.
Magnitude of an Electric Field: • Electromagnets: Magnetic Field Near a Current-
- Electromagnet = combination of an
• Force is proportional to the charge.
iron core with an insulated current-
Carrying Wire:
𝐹
• E=𝑄. carrying wire around it. • Right-hand rule:
• Magnitude (E) of electric field at a point = - When an iron object is in a magnetic - Imagine holding the conductor.
the force experienced per unit charge field of a strong magnet - the iron - Your thumb points in the direction of current.
placed at the point – measured in object becomes a magnet too - - Your other fingers are curled in the direction of the
newtons per coulomb (N.C-1). referred to as an induced magnet. magnetic field.
• Electric field at a point is given by: - The south pole of an induced magnet • Current-carrying solenoid:
𝑄
E = k𝑟 2 . is closest to the north pole of the - The magnetic field is directed from north to south outside
magnet – the magnet will attract the the solenoid.
induced magnet. - The magnetic field is directed south to north inside the
- Hard magnetic substances – require solenoid.
strong magnetic fields to be - If the direction of current is reversed, polarity is reversed.
magnetised – retain their magnetism. - Right-hand solenoid rule = imagine holding a solenoid in
- Soft magnetic substances – easily your right hand – fingers curled in the direction of the
magnetised but lose their magnetism current, and your thumb points in the direction of the
immediately after being removed from magnetic field inside the solenoid.
the magnetic field. - Increasing the current and the no. of turns in the coil
increases the magnetic field.
GR11 PS T3-C6 Mind Map Via Afrika Copyright © www.summariessa.co.za (DO NOT COPY)
