SPM Form 5 Physics

01 Force and Motion II
1.1 Resultant Force
3 Topics | 1 Quiz
1.1.1 Vector Quantities
1.1.2 Vector Addition
1.1 Resultant Force
1.1.1 Addition of Forces
1.2 Resolution of Forces
3 Topics | 1 Quiz
1.2.1 Vector Resolution
1.2.2 Inclined Plane
1.2 Resolution of Forces
1.2.1 Force Resolution
1.3 Forces in Equilibrium
2 Topics | 1 Quiz
1.3.1 Forces in Equilibrium
1.3 Forces in Equilibrium
1.3.1 Forces in Equilibrium
1.4 Elasticity
4 Topics | 4 Quizzes
1.4.1 Elasticity
1.4.2 Hooke’s Law
1.4.3 Spring
1.4 Elasticity
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
5 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 Pressure in Liquids
2.1.1 Liquid pressure
2.1.2 Liquid pressure – Numerical Problems
2.2 Atmospheric Pressure
8 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 Atmospheric Pressure
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
6 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 Gas Pressure
2.3.1 Gas Pressure – Numerical Problems
2.4 Pascal’s Principle
3 Topics | 1 Quiz
2.4.1 Pascal’s Principle
2.4.2 Applications of Pascal’s Principle
2.4 Pascal’s Principle
2.4.1 Pascal’s Principle
2.5 Archimedes’ Principle
3 Topics | 1 Quiz
2.5 Archimedes Principle
2.5 Application of Archimedes Principle
2.5 Archimedes’ Principle
2.5.1 Archimedes’ Principle
2.6 Bernoulli’s Principle
3 Topics | 1 Quiz
2.6 Bernoulli’s Principle
2.6 Application of Bernoulli’s Principle
2.6 Bernoulli’s Principle
2.6.1 Bernoulli’s principle
03 Electricity
3.1 Current and Potential Difference
5 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 Current and Potential Difference
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
8 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 Resistance
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
5 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 Electromotive Force (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
6 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 Electrical Energy and Power
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
6 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 Force on a Current-carrying Conductor in a Magnetic Field
4.1.1 Catapult Force
4.1.2 Motor
4.2 Electromagnetic Induction
8 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 Electromagnetic Induction
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
4 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 Transformer
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
3 Topics | 1 Quiz
5.1 Thermionic Emission
5.1 Cathode Ray
5.1 Electron
5.1.1 Cathode Ray
5.2 Semiconductor Diode
12 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 Semiconductor Diode
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
6 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 Transistor
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
10 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 Radioactive Decay
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
6.2 Nuclear Energy
6 Topics | 2 Quizzes
6.2.1 Nuclear Energy
6.2.2 Nuclear Fission
6.2.3 Chain Reaction
6.2.4 Nuclear Fusion
6.2.5 Generation of Electricity from Nuclear Fission
6.2 Nuclear Energy
6.2.1 Nuclear Energy
6.2.2 Nuclear reactor
07 Quantum Physics
7.1 Quantum Theory of Light
6 Topics
7.1.1 History of Quantum Physics
7.1.2 Black Body
7.1.3 Quantum of Energy
7.1.4 Wave Particles Duality
7.1.5 Problem Solving for Photon Energy and Power
7.1 Quantum Theory of Light
7.2 Photoelectric Effect
3 Topics
7.2.1 Photoelectric Effect
7.2.2 Characteristics of Photoelectric Effect
7.2 Photoelectric Effect
7.3 Einstein’s Photoelectric Theory
6 Topics
7.3.1 Einstein’s Photoelectric Theory
7.3.2 Work Function and Threshold Frequency for Photoelectric Effect
7.3.3 Generating Photoelectric Current in Photoelectric Circuit
7.3.4 Generating Photoelectric Current in Photoelectric Circuit
7.3.5 Applications of Photoelectric Effect
7.3 Einstein’s Photoelectric Theory
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3.4 Electrical Power

SPM Form 5 Physics 3.4 Electrical Energy and Power 3.4 Electrical Power

Power

  1. The electric power, P is defined as the rates of energy that supply to the circuit ( or the rates of work been done ) by sources of electric.
  2. The unit of electric power is the watt (W).
  3. One watt of power equals the work done in one second by one volt of potential difference in moving one coulomb of charge.
  4. The electrical power of an electric circuit component can be found from the following equations:

    Where
    P = power
    t = time
    I = current
    V = potential difference
    R = resistance

Example 1:
A current of 0.50A flows through a 100Ω resistor. What is the power lost in the resistor?

Answer:

Example 2
An electric iron has a heating element of resistance 50Ω. If the operating current flowing through it is 4A, calculate the heat energy produced in 2 minutes.

Answer:
Power of the iron,

Heat energy produced,

Example 3
What is the power dissipated in a 4Ω light bulb connected to a 12V battery? What is the power dissipated in a 2Ω light bulb connected to the same battery? Which bulb is brighter?

Answer:
Assume that the bulbs are resistor

Power dissipated in the 4Ω resistor,

Power dissipated in the 2Ω resistor,

The power of the 2Ω bulb is higher, hence it is brighter.

[Conclusion: The lower the load resistance in a circuit, the greater the power dissipated in the circuit]

Example 4

An ideal battery with e.m.f. 12 V is connected in series to two bulbs with resistances R1 = 4Ω and R2 = 2Ω  What is the current in the circuit and the power dissipation in each bulb?

Answer:
Potential difference across the 2 resistors, V = 12V
Equivalence resistance of the 2 resistors, R = 4 + 2 = 6Ω
Current in the circuit,

Power dissipated in R1

Power dissipated in R2

[Conclusion: In a series connection, the greater the resistance of a resistor, the greater the power dissipated]

Example 5

The figure above shows that an ideal battery is connected in parallel to two resistors with resistances 2Ω and 4Ω. Find the power dissipated in
a. the 4Ω resistor
b. the  2Ω resistor

Answer:
a. The potential difference across the 2 resistors = 12V
The power of the 2Ω resistor,

b.
The power of the 4Ω resistor,

[Conclusion: In a parallel connection, the lower the resistance, the greater the power of the resistor.]

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