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
0/3
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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Measurement of Length and Distance

Length is a measure of how long an object is or the distance between two points in space. It is used for identifying the size of an object or distance from one point to another. The length of an object is its extended dimension, that is, its longest side. For example, the length of the ruler below is 15 cm.

The standard unit (SI) of length based on the metric system is a meter (m). According to the length that needs to be measured, we can convert a meter into various units like millimeters (mm), centimeter (cm), and kilometer (km).

Therefore:

  • 1 km = 1000 m
  • 1 Hm = 100 m
  • 1 Dm= 10 m
  • 1 mm = 0.001 m

Centimeters and millimeters help measure smaller lengths and meters and kilometers help measure larger lengths like distance.

The SI unit for length is the metre (m).

One hundred equal divisions of a meter give a centimeter. It is written as ‘cm’. That is,  

1 m = 100 cm

One thousand equal divisions of kilometer give a meter. That is,

1 km = 1,000 m

According to the length conversion charts, the different units of lengths and their equivalents are given below:

A kilometer (km), meter (m), and centimeter (cm) are the commonly used units of length.

Conversion of these units is done using the given formula.

 Length is measured using a metre rule (100 cm), tape measure (100 m, 300 m, 500 m),calipers. similarly, length can be measured using Vernier calipers  and Micrometer screw gauge

  1. Meter Rule:
    Meter rule is used to measure distance on paper. It is calibrated in millimeters, centimeters, . Some meter rules are calibrated in inch or feet. The accuracy of meter rule is 0.1 cm or 1.0 mm
    With a  meter rule ,distance is measured starting from the zero reference mark to any required length.  The measured distance or length is read and recorded. 

 Callipers:
Callipers are not used to measure distance or length directly as the case is in meter rule. The claws of the callipers are adjusted to touch the edges of the object that is being measured. The span of the jaws of the callipers is then measured against a calibrated scale or meter rule to determine or estimate the size of the measured distance or length.

3.The Vernier Calipers

The vernier calipers may be used to measure outer dimensions of objects (using the main jaws), inside dimensions (using the smaller jaws at the top), and depths (using the stem).

A Vernier calliper has two scale : the main scale and the Vernier scale.
a. The main scale:
The calibrations or scales of the main scale of Vernier callipers vary depending on the range of measurement that the Vernier callipers are meant to measure. .
b.   The vernier scale:
The vernier scale of a vernier calliper is obtained by dividing a 9mm length into 10 equal divisions or intervals such that each divisions is 0.9mm or 0.09cm.

The accuracy of a vernier caliper is 0.1mm or 0.01cm. This means the that the smallest distance that a vernier calliper can measure is 0.1mm or 0.01cm
 How to use a  vernier calliper:
 Step I.   Read and record the reading of the main scale
 Step II.  Read and record the reading of the vernier scale at the point    where the main scale and the vernier scale coincide.
 Step III. Multiply the reading of the vernier scale by the accuracy of the vernier scale which is 0.01cm.
Step IV. Add the result of step III to the main scale reading of step I to get the final answer which is the reading of the vernier calliper.

Example 1:
What is the reading of the vernier calliper as shown in the figures below?

Solution:
Reading of main scale.           =     10.0   cm
Reading of vernier scale        =     2                  
Reading of vernier scale x accuracy of vernier calliper  

=    2 x 0.01 cm  =    0.02   cm
Add the result of step III and step I to get the reading.  

=    10.0 cm + 0.02 cm
Therefore, the reading of vernier calliper is  10.02cm              

Example 2:
Estimate the reading of the vernier calliper as shown in the figure below:

Solution:
Reading of main scale.           =     4.3   cm
Reading of vernier scale        =     5                  
Reading of vernier scale x accuracy of vernier calliper  

=     5 x 0.01 cm  =    0.05   cm
Add the result of step III and step I to get the reading.    

  =    4.30 cm + 0.05 cm

Therefore,  the   reading of vernier calliper is  4.35 cm.    

Micrometer Screw Gauge

The micrometer screw gauge is used to measure even smaller dimensions than the vernier callipers. The micrometer screw gauge also uses an auxiliary scale (measuring hundredths of a millimetre) which is marked on a rotary thimble. Basically it is a screw with an accurately constant pitch (the amount by which the thimble moves forward or backward for one complete revolution).  

Just like a vernier calipers, a micrometer screw gauge has two scales : the main scale and the vernier scale.
     a. The main scale:
 The main scale of a micrometer is calibrated in mm. The     calibrations of the main scale of micrometer screw gauge vary depending on the range of measurement that the micrometer screw gauges are meant to measure.
    b.The thimble scale:
The thimble scale has 50 equal divisions. Each divisions is obtained by dividing 5 by 10. The thimble scale move a distance of 0.5mm along the main scale when it make 1 revolution by turning round once. One division on the thimble scale equal to 0.5/50 which equal to 0.01mm on the main scale.

The accuracy of a micrometer screw gauge is 0.01mm or 0.001cm. This means the that the smallest distance that a micrometer screw gauge can measure is 0.01mm or 0.001cm.
How to use  a micrometer screw gauge :
Step I. Read and record the reading of the main scale
Step II. Read and record the reading of the thimble scale at the point where the main scale and the thimble scale coincide.
Step III. Multiply the reading of the thimble scale by the accuracy of the micrometer scale which is 0.01mm
Step IV.   Add the result of step III to the main scale reading of step I to get the final answer which is the reading of the micrometer.

 Example 1.:
What is the readings of the reading of the micrometer meter screw gauges as shown in the figures below?

Solution:
Reading of main scale.         =   4.50 mm
Reading of thimble scale      =    10              

Reading of thimble scale x accuracy of micrometer 

 = 10 x 0.01 = 0.10 mm
Add the result of step III and step I to get the reading of the micrometer screw gauge.  

=  4.50 + 0.10   =    4.60 mm
Reading of micrometer   =     4.60 mm  

Example2.:
What is the readings of the reading of the micrometer meter screw gauges as shown in the figures below?

Solution:
Reading of main scale.         =   22.0 mm
Reading of thimble scale      =   33              

Reading of thimble scale x accuracy of micrometer 

 = 33 x 0.01 =   0.33 mm
Add the result of step III and step I to get the reading of the micrometer screw gauge.                        

=  22.0 + 0.33   =   22.33 mm
Reading of micrometer screw gauge    =     22.33 mm

Example 3.:
What is the readings of the reading of the micrometer meter screw gauges as shown in the figures below?

Solution:
Reading of main scale.         =   3.25 mm
Reading of  thimble scale      =  13  
Reading of thimble scale x accuracy of micrometer 

 = 13 x 0.01 = 0.13 mm
Add the result of step III and step I to get the reading of the micrometer screw gauge.    

=  3.25 + 0.13=  3.38 mm
Reading of the micrometer meter screw guage    

=     3.38 mm  

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