SPM Physics Revision

6.3 Image Formation by Lenses
5 Topics | 2 Quizzes
6.3.1 Power of Lenses
6.3.2 Convex Lens
6.3.3 Characteristics of the Image Formed by a Convex Lens
6.3.4 Concave Lens
6.3.5 Characteristics of the Image Formed by a Concave Lens
6.3.1 Fundamental of Lenses
6.3.2 Lens – Characteristic of Images
6.4 Thin Lens Formula
1 Topic | 1 Quiz
6.4.1 The Lens Equation
6.4.1 Lens – Numerical Problems
6.5 Optical Instruments
4 Topics | 4 Quizzes
6.5.1 Magnifying Glass
6.5.2 Optical Instruments – Projector
6.5.3 Optical Instruments – Astronomical Telescope
6.5.4 Optical Instruments – Compound Microscope
6.5.1 Camera
6.5.2 Projector
6.5.3 Astronomical Telescope
6.5.4 Compound microscope
6.6 Image Formation by Spherical Mirrors
2 Topics | 1 Quiz
6.6.1 Curved Mirror
6.6.2 Drawing Ray Diagram for Concave Mirror
6.6.1 Curved Mirror
01 Force and Motion II
1.1 Resultant Force
2 Topics | 1 Quiz
1.1.1 Vector Quantities
1.1.2 Vector Addition
1.1.1 Addition of Forces
1.2 Resolution of Forces
2 Topics | 1 Quiz
1.2.1 Vector Resolution
1.2.2 Inclined Plane
1.2.1 Force Resolution
1.3 Forces in Equilibrium
1 Topic | 1 Quiz
1.3.1 Forces in Equilibrium
1.3.1 Forces in Equilibrium
1.4 Elasticity
3 Topics | 4 Quizzes
1.4.1 Elasticity
1.4.2 Hooke’s Law
1.4.3 Spring
1.4.1 Hooke’s Law
1.4.2 Graph of Elasticity
1.4.3 Factors Affecting the Stiffness of Spring
1.4.4 Elastic Potential Energy
02 Pressure
2.1 Pressure in Liquids
4 Topics | 2 Quizzes
2.1.1 Pressure in Liquid
2.1.2 Pressure in Liquid – The U-Tube
2.1.3 Characteristics of Liquid Pressure
2.1.4 Applications of Pressure in Liquid
2.1.1 Liquid pressure
2.1.2 Liquid pressure – Numerical Problems
2.2 Atmospheric Pressure
7 Topics | 3 Quizzes
2.2.1 Atmospheric Pressure
2.2.2 Proof of Existence of Atmospheric Pressure
2.2.3 Applications of Atmospheric Pressure
2.2.4 Instruments to Measure Atmospheric Pressure
2.2.5 Simple Mercury Barometer
2.2.6 Fortin Barometer
2.2.8 Anaroid Barometer
2.2.1 Gas Pressure and Atmospheric Pressure
2.2.2 Using Barometer to find atmospheric pressure
2.2.3 Atmospheric pressure – Numerical problems
2.3 Gas Pressure
5 Topics | 1 Quiz
2.3.1 Gas Pressure
2.3.2 Instruments Used to Measure Gas Pressure
2.3.3 Bourdon Gauge
2.3.4 Manometer
2.3.5 Gas Trapped in a Capillary Tube
2.3.1 Gas Pressure – Numerical Problems
2.4 Pascal’s Principle
2 Topics | 1 Quiz
2.4.1 Pascal’s Principle
2.4.2 Applications of Pascal’s Principle
2.4.1 Pascal’s Principle
2.5 Archimedes’ Principle
2 Topics | 1 Quiz
2.5 Archimedes Principle
2.5 Application of Archimedes Principle
2.5.1 Archimedes’ Principle
2.6 Bernoulli’s Principle
2 Topics | 1 Quiz
2.6 Bernoulli’s Principle
2.6 Application of Bernoulli’s Principle
2.6.1 Bernoulli’s principle
03 Electricity
3.1 Current and Potential Difference
4 Topics | 4 Quizzes
3.1 Current
3.1 Potential and Potential Difference
3.1 Ohm’s Law – Relationship Between Current and Potential Difference
3.1 Resistance
3.1.1 Electric Field and Charge Flow 1 – Electric Charge
3.1.2 Electric Field and Charge Flow 2 – Electric Field
3.1.3 Current
3.1.4 Potential Difference
3.2 Resistance
7 Topics | 5 Quizzes
3.2 Resistance in series and parallel Circuit
3.2 Finding Resistance of an Individual Resistor
3.2 Current in a Circuit
3.2 Potential and Potential Difference in a Circuit
3.2 Finding Current in a Series Circuit
3.2 Finding Current in a Parallel Circuit
3.2 Finding Potential Difference in a Series Circuit
3.2.1 Ohm’s Law
3.2.2 Resistance and Resistivity
3.2.3 Series and Parallel Circuit 1 – Finding Effective Resistance
3.2.4 Series and Parallel Circuit 2 – Finding Current
3.2.5 Series and Parallel Circuit 3 – Finding Potential Difference 1
3.3 Electromotive Force (e.m.f ) and Internal Resistance
4 Topics | 2 Quizzes
3.3 Electromotive Force
3.3 Difference between Electromotive Force and Potential Difference
3.3 Internal Resistance and Potential Difference Drop
3.3 Measuring e.m.f. and Internal Resistance
3.3.1 EMF and Internal Resistance 1 – Fundamental
3.3.2 EMF and Internal Resistance 2 – Finding EMF and Internal Resistance
3.4 Electrical Energy and Power
5 Topics | 3 Quizzes
3.4 Electrical Energy
3.4 Electrical Power
3.4 Sum of the Power
3.4 Power Rating
3.4 Efficiency of Electrical Appliance
3.4.1 Electrical Energy and Power 1 – Electrical Energy
3.4.2 Electrical Energy and Power 2 – Electrical Power
3.4.3 Electrical Energy and Power 3 – Electrical Energy Consumption
04 Electromagnetism
4.1 Force on a Current-carrying Conductor in a Magnetic Field
5 Topics | 2 Quizzes
4.1 Turning Effect of a Current Carrying Coil in a Magnetic Field
4.1 Application of the Force on a Current Carrying Conductor in a Magnetic Field – Moving Coil Meter
4.1 Direct Current Motor
4.1 Application of the Force on a Current Carrying Conductor in a Magnetic Field – Loudspeaker
4.1 Force between 2 Current-Carrying Conductors
4.1.1 Catapult Force
4.1.2 Motor
4.2 Electromagnetic Induction
7 Topics | 4 Quizzes
4.2 Electromagnetic Induction
4.2 Induced EMF and Current in a Straight Wire
4.2 Induced EMF and Current in a Solenoid
4.2 Direct Current Generator
4.2 Alternating Current Generator
4.2 Direct Current and Alternating Current
4.2 Root Mean Square Voltage/Current
4.2.1 Electromagnetic Induction
4.2.2 Direction of Current
4.2.3 Induction 3 – Additional Question for Induction
4.2.4 Induction 4 – Generator
4.3 Transformer
3 Topics | 3 Quizzes
4.3 Types of Transformer
4.3 Factors That Affect the Efficiency of a Transformer
4.3 Generation of Electricity
4.3.1 Transformer 1 – Fundamental
4.3.2 Transformer 2 – Numerical Problems
4.3.3 Transformer 3 – Sources of energy loss
05 Electronics
5.1 Electron
2 Topics | 1 Quiz
5.1 Thermionic Emission
5.1 Cathode Ray
5.1.1 Cathode Ray
5.2 Semiconductor Diode
11 Topics | 5 Quizzes
5.2 Free Electron and Hole
5.2 Semiconductors
5.2 Flows of Free Electrons and Holes
5.2 Doping a Semiconductor
5.2 N-Type Semiconductor
5.2 P-Type Semiconductor
5.2 N-Type and P-Type Semiconductor – Summary
5.2 Forward Bias and Reverse Bias
5.2 Diodes as Rectifiers
5.2 Full Wave Rectification
5.2 Capacitor Smoothing
5.2.1 Semiconductor
5.2.2 Extrinsic Semiconductor
5.2.3 Semiconductor Diode 1
5.2.4 Semiconductor Diode 2 – Forward Bias and Reverse Bias
5.2.5 Semiconductor Diode 3 – Diode as a Rectifier
5.3 Transistor
5 Topics | 3 Quizzes
5.3 Transistors
5.3 Connection of Transistor
5.3 Current in Transistor
5.3 Transistor as a Current Amplifier
5.3 Transistor as an Automatic Switch
5.3.1 Transistor
5.3.2 Application of Transistor 1 – Amplifier
5.3.3 Application of Transistor – Automatic Switch
06 Nuclear Physics
6.1 Radioactive Decay
9 Topics | 6 Quizzes
6.1.1 The Composition of the Nucleus
6.1.2 Radioactivity
6.1.3 Types of Radioactive Emission
6.1.4 Characteristics of Radioactive Emission
6.1.5 Radioactive Decay – Alpha Decay
6.1.6 Radioactive Decay – Beta Decay
6.1.7 Radioactive Decay – Gamma Decay
6.1.8 Radioactive Decay – Series Decay
6.1.9 Half-life
6.1.1 Introduction to radioactivity 1 – Fundamental
6.1.2 Comparison of the 3 Radioactive Emissions
6.1.3 Radioactive Decay
6.1.4 Series Decay
6.1.5 Introduction to Half-Life
6.1.6 Numerical Problems Related to half-life
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4.1 Direct Current Motor

SPM Physics Revision 4.1 Force on a Current-carrying Conductor in a Magnetic Field 4.1 Direct Current Motor
  1. An electric motor converts electrical energy to kinetic energy.
  2. The diagram above shows the structure of a simple direct current motor (DC motor).
  3. It consists of a rectangular coil of wire placed between 2 permanent magnets.
  4. The coil is soldered to a copper split ring known as a commutator. 2 carbon brushes are held against the commutator.
  5. The function of the brush is to conduct electricity from the external circuit to the coil and allow the commutator to rotate continuously.
  6. The function of the commutator is to change the direction of the current in the coil and hence change the direction of the couple (the 2 forces in opposite direction) in every half revolution. This is to make sure that the coil can rotate continuously.
  7. The operation principle of a direct current motor is explained in detail in the second Youtube video below.

Recommended Video
SPM Physics – Direct Current Motor 

In this video, our tutor explains the important point that SPM students need to know to prepare for their exam.

This video shows how the commutator changes the direction of the current in the coil, and hence change the direction of the force in every half revolution. Pay attention to the change of direction of the force in every half revolution.

This is a very long video, discussing how the force is produced by the interaction between a current-carrying conductor in a magnetic field and its application in the direct current motor.

External Resources

Physics Animation

DC Motor

External Link

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