Course Content
Properties of Matter
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Explain the three states of matter. 2.Explain phenomenon of surface tension. 3.Explain gas laws.
0/3
Introduction
States Of Matter
Gas Laws
Measurement
OBJECTIVES By the end of this topic , the trainee should be able to: 1.State the basic and derived quantities of measurements 2.Describe quantities of measurements 3.State the SI units of quantities of measurements and their sub-multipliers 4.Convert units from one to another
0/4
Introduction
Measurement of Length and Distance
  Measurement of Mass and weight
 Measurement of Volume and Density
Pressure
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Define pressure 2.Determine pressure in solids and fluids 3.Explain the type of instruments used in measurement of pressure of gases 4.Explain transmission of presure in liquids
0/2
Introduction
Measuring Pressure
Force
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define force and its SI units 2.Explain types of force 3.Measure force 4.Work out calculations involving force 5.Explain Hooke’s law
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Force
Friction Force
Centrifugal and Centripetal Force
Hooke’s Law
Hooke's Law  is a law named after 17th century British physicist Robert Hooke, who sought to demonstrate the relationship between the forces applied to a spring and its elasticity.
0/1
Hooke’s Law
Moments
OBJECTIVES By the end of this topic, the trainee should be able to: 1. Define moments of a force 2.Explain principles of moments 3.Explain statics , dynamics and kinematics
0/1
Moments
Velocity and Speed
OBJECTIVES By the end of this topic , the trainee should be able to : 1.Define speed and velocity 2.Explain types of motion 3.Determine Linear Determine Circular Motion
0/1
Velocity and Speed
Work and Power
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Define work and power 2.Work out calculations involving work and power
0/1
Work and Power
Energy
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define energy 2.Explain forms of energy 3.Explain law of conservation of energy
0/1
Energy
Motion
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define motion 2.Explain causes of motion 3.Explain types of motion 4.Describe linear and circular motion
0/3
Introduction
Linear Motion 
Circular Motion
Newton’s Laws of Motion
OBJECTIVES By the end of this topic, the trainee should be able to: 1.State Newton’s laws of motion 2.Explain relationships between mass and inertia 3.Explain significance of Newton’s laws of motion
0/1
Newton’s Laws of Motion
Heat and Heat Transfer
OBJECTIVES By the end of this topic, the trainee should be able to 1.Define temperature and heat 2.Describe instruments used to measure temperature 3.Explain modes of heat transfer 4.Explain factors that influence heat transfer 5.Explain heat capacity, specific heat capacity and specific latent heat of substances 6. Work out calorimetric calculations
0/5
Introduction
Instruments Used For Measuring Temperature  
Heat Transfer
Measuring The Quantity Of Heat
Heat and Changes of State
Light
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Define light and its properties 2.Explain types of mirrors and lenses 3.Explain reflection and refraction of light 4. Explain the lens formulae
0/10
Introduction
Mirrors
Reflection 
Mirror Equation
Image Formation By Convex Mirror
Refraction Of Light
 Refractive index
Thin Lenses
The lens formula
 Uses of lenses on optical devices
WAVES
OBJECTIVES By the end of this topic , the trainee should be able to : 1. Define waves 2.Explain types of waves 3.Explain characteristics and properties of waves 4.Explain rectilinear propagation of waves 5.Describe refraction of waves 6.Describe sound and sound waves
0/6
Introduction
Electromagnetic Wave
Electromagnetic Wave
Properties of Waves
Rectilinear Propagation Of Waves
Sound and Sound Waves
Electrostatics
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Define electrostatics 2. Describe the working of electroscopes 3.Describe different methods of charging a body 4.Explain electric fields 5.Describe charge distribution on conductors’ surface 6. Describe capacitors and capacitance
0/5
Introduction
Gold Leaf Electroscope
Electric Fields
Charge Distribution on Conductors’ Surface
Capacitors And Capacitance
Magnetism and Electromagnetism
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define magnetism 2.Identify magnetic and non- magnetic materials 3.Explain properties of magnets 4.Describe magnetic field patterns 5.Describe making magnets 6.Explain domain theory of magnets 7.Describe magnetic effect of an electric current. 8. Describe electromagnets and electromagnetism 9.Describe electromagnetic induction
0/6
Introduction
Magnetic Field Patterns.
Making Magnets
Magnetic Effect of An Electric Current.
Electromagnetism 
Electromagnetic Induction
Current Electricity
CURRENT ELECTRICITY OBJECTIVES By the end of this topic, the trainer should be able to: 1. Define current and electricity 2.Electric potential difference 3.Explain use of a meters, voltmeters and resistors 4.Explain ohm’s law 5. Explain Electromotive force and internal resistance 6.Describe production of electric current 7.Describe simple cells, Leclanche’ cell, dry cells and lea-acid accumulators 8.Describe mains electricity 9.Describe domestic wiring
0/6
Introduction
Electric Potential Difference And Electric Current
Resistors and Resistance
Production Of Electric Current:
Heating Effect Of An Electric Current
Mains Electricity
Electromagnetic Spectrum
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Define magnetic spectrum 2. Explain properties of electromagnetic waves 3. Describe applications of electromagnetic radiation
0/2
Introduction
Properties and Application of Electromagnetic Waves
Radioactivity
OBJECTIVES By the end of this topic, the trainee should be able to: 1. Define radioactivity 2.Classify radiations 3.Explain the properties of radiation materials 4.Describe nuclear fission and nuclear fusion 5.Describe methods for detecting nuclear radiation 6.Describe activity and half-life of elements 7. Discuss hazards of radioactivity and their precautions 8. Outline the applications of radioactivity
0/4
Introduction
Nuclear Fission
Activity and Half-Life Of Elements
Applications Of Radioactivity
Cathode and X-Rays
OBJECTIVES By the end of this topic, the trainee should be able to: 1. Define cathode and X- rays 2.Explain production of cathode and X- ray 3.Explain properties of cathode and X- ray 4.Describe cathode ray oscilloscope (CRO) 5. Describe the applications of Cathode and X-rays
0/2
Cathode Rays
X-Rays
Physics Techniques For Science Laboratory Technicians
About Lesson

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Capacitors And Capacitance

A capacitor is a two-terminal electrical device that can store energy in the form of an electric charge. It consists of two electrical conductors that are separated by a distance.  The space between the conductors may be filled by vacuum or with an insulating material known as a dielectric. The ability of the capacitor to store charges is known as capacitance.

Capacitors store energy by holding apart pairs of opposite charges. The simplest design for a capacitor is a parallel plate, which consists of two metal plates with a gap between them. But, different types of capacitors are manufactured in many forms, styles, lengths, girths, and materials.

How Does A Capacitor Work?

For demonstration, let us consider the most basic structure of a capacitor – the parallel plate capacitor. It consists of two parallel plates separated by a dielectric.

 When we connect a DC voltage source across the capacitor, one plate is connected to the positive end (plate I) and the other to the negative end (plate II). When the potential of the battery is applied across the capacitor, plate I become positive with respect to plate II. The current tries to flow through the capacitor at the steady-state condition from its positive plate to its negative plate. But it cannot flow due to the separation of the plates with an insulating material.

An electric field appears across the capacitor. The positive plate (plate I) accumulates positive charges from the battery, and the negative plate (plate II) accumulates negative charges from the battery.  After a point, the capacitor holds the maximum amount of charge as per its capacitance with respect to this voltage. This time span is called the charging time of the capacitor.

When the battery is removed from the capacitor, the two plates hold a negative and positive charge for a certain time. Thus, the capacitor acts as a source of electrical energy.

If these plates are connected to a load, the current flows to the load from Plate I to Plate II until all the charges are dissipated from both plates. This time span is known as the discharging time of the capacitor.

How Do You Determine The Value Of Capacitance?

The conducting plates have some charges Q1 and Q2 (Usually, if one plate has +q, the other has –q charge). The electric field in the region between the plates depends on the charge given to the conducting plates. We also know that potential difference (V) is directly proportional to the electric field hence we can say,

Q∝V

Q=CV

C=Q/V

This constant of proportionality is known as the capacitance of the capacitor.

Capacitance is the ratio of the change in the electric charge of a system to the corresponding change in its electric potential.

The capacitance of any capacitor can be either fixed or variable, depending on its usage. From the equation, it may seem that ‘C’ depends on charge and voltage. Actually, it depends on the shape and size of the capacitor and also on the insulator used between the conducting plates.

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