7/28/2019 Physics Form 4 Chapter 1 Introduction To Physics
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Chapter 1 Introduction to Physics
Physics is the study of natural phenomena and theproperties of
matter.
Fields of physics:1. Force and motion: investigates the action
of
force and motion.
2. Heat: studies the influence of heat on thedifferent types of
matter.
3. Light: explains the different phenomena due tolight.
4. Waves: understands the properties of differenttypes of waves
and their uses.
5. Electricity and electromagnetism: investigatesthe
interactions of electric and magnetic fields.
6. Electronics: studies the use of electronic devicesin various
fields.
7. Nuclear physics: study of nuclear structure andtheir
applications.
Physical quantities are the physical characteristics thatcan be
measured.
Base quantities are quantities that cannot be defined in
terms of other base quantities.
Base quantity Quantity
symbol
SI unit Symbol
Length metre m
Mass m kilogram kg
Time t second s
Electric current I ampere A
Temperature T kelvin K
Derived quantity is a quantity that is derived by
multiplication or division or both of base quantities.
Prefixes is a number of the form 10n
(where n is an
integer) placed in front of a unit of measurement andacts as its
multiplications factor.
Volume Density Energy
Acceleration Electric
charge
Velocity The magnitude of a physical quantity can be
expressed in standard form or scientific notation,that is in
power of 10: A x 10n, where 1 A < 10 and
n is an integer.
Force Power Momentum
Prefix Symbol Multiplications factor Prefix Symbol
Multiplications factor
Tetra T 1012
Centi c 10-2
Giga G 109
Milli m 10-3
Mega M 106
Micro 10-6
Kilo k 103
Nano n 10-9
Deci d 10-
Pico p 10-
Scalar vector are quantities that have magnitude but
nodirection.
Vector quantities are quantities that have bothmagnitude and
direction.
Displacement
VelocityForce
AccelecartionMomentum
Length Time
Area VolumeDistance Speed
Work Energy
Temperature Density
Accuracy of a measurement is how close the value of the
measurement to the actual value.
Consistency in measurements refers to how little
deviation there is among the measurements madewhen a quantity is
measured several times.Sensitivity of an instrument is its ability
to detect a small
change in the quantity to be measured.
An error is the difference between the actual magnitudeof a
physical quantity and the value obtained in themeasurement.
Types of errors in measurement:a. Systematic error is an error
that is either too
high or too low from the actual value. Dueto: zero error;
incorrectly calibrated scale;wrong assumption; repeating errors
b. A random error has non constant size oferror that is
sometimes too high or too low.Due to: parallax error; changes
insurroundings
A parallax error is the error in reading a measurementbecause
the eye is in the wrong position.
Zero error is the error when measurements do not startfrom
exactly zero.
observing
phenomena
identifying
problem
identifying
the
variables
forming
hypothesis
planning
investigation
carrying
out theinvestigation
observing
andcollecting
data
analysing
andinterpreting
data
making
conclusion
Scientific method
