Chapter 1: Introduction to Physics

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Chapter 1 Introduction to Physics

• 1.1 Understanding Physics

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1.1 Understanding Physics

• 1. Like all sciences, physics is based on
  experimental observations and quantitative
  measurements. 

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1.1 Understanding Physics

• 2. Historically, until nineteenth century,
  physics was called natural philosophy.
•  

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1.1 Understanding Physics

• 3. Physics is a branch of science concerning
  study of natural phenomena, that is, properties
  of matter and energy.
•  

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1.1 Understanding Physics

• 4. Some examples of natural phenomena are
• (a) sunrise and sunset,
• (b) lightning and thunder,
• (c) rainbow and blue sky,
• (d) earthquake and tsunami.

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Field of study in Physics

• 1 In general, physics is concerned with the
  study of energy and the properties and structure
  of matter.
•  

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Field of study in Physics

• 2 The fields of study in physics can be divided
  into classical physics and modern physics.

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Field of study in Physics

• 3 Classical physics deals with questions
  regarding motion and energy. It includes five
  important areas mechanics (forces and motion),
  heat, sound, electricity and magnetism, and
  light.
•  

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Field of study in Physics

• 4 Modern physics concentrates on scientific
  beliefs about the basic structure of the material
  world. Its major fields include atomic, molecular
  and electron physics, nuclear physics, particle
  physics, relativity, origin of the universe, and
  astrophysics.

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Chapter 1

• 1.1.2 Understanding Base Quantities and rived
  Quantities

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Base Quantities

• 1. Physical quantities are quantities that can
  be measured.

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Base Quantities

• 2. A physical quantity can be represented by a
  symbol of the quantity, a numerical value for the
  magnitude of the quantity and the unit of
  measurement of the quantity.
•  

Length, l 1.67 m
m - unit
l - symbol
1.67is the value
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Base Quantities

• 3. Base quantities are physical quantities that
  cannot be defined in terms of other quantities.
•  

Base quantity Length
Derived quantity Area length x length
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Base Quantities

• 4. Table 1.1 shows five base quantities and
  their respective SI units.
•  

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Base Quantities
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Derived Quantities

• 1 Derived quantities are physical quantities
  derived from base quantities by multiplication or
  division or both. The unit for a derived quantity
  is known as a derived unit.

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Derived Quantities

• 2 Table 1.2 shows some examples of derived
  quantities and their corresponding derived units.
  Several derived units are complex. Special names
  are substituted for these units. For example, the
  unit for the derived quantity, force, is the
  newton (N).

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Derived Quantities
Acceleration ms2
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Scientific Notation

• 1 Scientists have developed a shorter method of
  expressing very large or very small numbers. This
  method is called scientific notation or standard
  form.

Distance from house to school 5 000 m
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Scientific Notation

• 2 Scientific notation is based on powers of the
  base number 10. The scientific notation in
  standard form is written as
•  
• A x 10n
• where
• (a) 1 ? A lt 10 and A can be an integer or decimal
  number.
• (b) n is a positive integer for a number greater
  than one or a negative integer for a number less
  than one.

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Prefixes

• 1. Prefixes are used to simplify the description
  of physical quantities that are either very big
  or very small.

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Prefixes

• 2. It is not easy to figure out a distance of
  100 000 mm. Neither it is easy to imagine the
  size of an atom which has a radius of 0.0000005 m.

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Prefixes

• 3. Table 1.3 lists some commonly used SI
  prefixes.

Ram 512 Mb
HD 80 Gb
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Prefixes