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.
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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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 Refractive index

  Refractive index (n) is the constant of proportionality in Snell’s law; hence

  • Sin i/ sin r = n
  •  Therefore sin i/sin r=n=1/sin r/sin i

 Examples

  1. Calculate the refractive index for light travelling from glass to air given that ang= 1.5

 Solution

 gna= 1/ang = 1/1.5=0.67

  1. Calculate the angle of refraction for a ray of light from air striking an air-glass interface, making an angle of 600 with the interface. (ang= 1.5)

Solution

 Angle of incidence (i) = 900-600=300

 1.5=sin 30o/sin r, sin r =sin 300/ 1.5=0.5/1.5

 Sin r=0.3333, sin-10.3333= 19.50

R= 19.50

 Refractive index in terms of velocity.

Refractive index can be given in terms of velocity by the use of the following equation;

 1n2 = velocity of light in medium 1/velocity of light in medium 2

 When a ray of light is travelling from vacuum to a medium the refractive index is referred to as absolute refractive index of the medium denoted by ‘n’

 Refractive index of a material ‘n’=velocity of light in a vacuum/velocity of light in material ‘n’

The absolute refractive indices of some common materials is given below

 Examples 1. A ray of light is incident on a water-glass interface as shown. Calculate ‘r’. (Take the refractive index of glass and water as 3/2 and 4/3 respectively)

  1. The refractive index of water is 4/3 and that of glass is 3/2. Calculate the refractive index of glass with respect to water.

Solution

  •  wng= gna×ang, but wna = 1/ anw=3/4
  •  wng=3/4×3/2=9/8= 1.13

 Real and apparent depth

Consider the following diagram

 The depth of the water OM is the real depth, and the distance IM is known as the apparent depth. OI is the distance through which the coin has been displaced and is known as the vertical displacement.

The relationship between refractive index and the apparent depth is given by;

 Refractive index of a material=real depth/apparent depth

 NB

This is true only if the object is viewed normally.

 Example

 A glass block of thickness 12 cm is placed on a mark drawn on a plain paper.

The mark is viewed normally through the glass. Calculate the apparent depth of the mark and hence the vertical displacement. (Refractive index of glass =3/2)

 Solution

  • ang= real depth/apparent depth
  • apparent depth= real depth/ ang=(12×2)/3= 8 cm
  •  vertical displacement= 12-8=4 cm

Applications of refractive index

 Total internal reflection

This occurs when light travels from a denser optical medium to a less dense medium. The refracted ray moves away from the normal until a critical angle is reached usually 900 where the refracted ray is parallel to the boundary between the two media.

 If this critical angle is exceeded total internal reflection occurs and at this point no refraction occurs but the ray is reflected internally within the denser medium.

Relationship between the critical angle and refractive index.

Consider the following diagram

  • ·

 From Snell’s law

  • gnw = sin C/sin 900,but ang = 1/gna since sin 900 = 1
  • Therefore ang= 1/sin C, hence sin C=1/n or n=1/sin C

Example

 Calculate the critical angle of diamond given that its refractive index is 2.42

 Solution

  Sin C= 1/n=1/ 2.42= 0.4132= 24.40

 Effects of total internal reflection

  1. Mirage: These are ‘pools of water’ seen on a tarmac road during a hot day.

 They are also observed in very cold regions but the light curves in opposite direction such that a polar bear seems to be upside down in the sky.

  1. Atmospheric refraction: the earths’ atmosphere refracts light rays so that the sun can be seen even when it has set. Similarly the sun is seen before it actually rises.

Applications of total internal reflection

  1. Periscope: a prism periscope consists of two right angled glass prisms of angles 450,900 and 450 arranged as shown below. They are used to observe distant objects.
  • ·
  1. Prism binoculars: the arrangement of lenses and prisms is as shown below. Binoculars reduce the distance of objects such that they seem to be nearer.
  1. Pentaprism: used in cameras to change the inverted images formed into erect and actual image in front of the photographer.
  2. Optical fibre: this is a flexible glass rod of small diameter. A light entering through them undergoes repeated internal reflections.

 They are used in medicine to observe or view internal organs of the body

  • ·
  1. Dispersion of white light:

the splitting of light into its constituent colours is known as dispersion. Each colour represents a different wavelength as they strike the prism and therefore refracted differently as shown.

  • ·
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