2. 1.2.1 Base Quantities
1.2.2 Derived Quantities
1.2.3 Prefixes
1.2.4 Scientific Notation
1.3 Scalar and Vector Quantities
1.4.0 Measurements and Error
1.4.1 Consistency, Accuracy and Sensitivity
1.4.2 Vernier Caliper
1.4.3 Micrometer Screw Gauge
1.4.4 Ruler, Thermometer, Stopwatch, Ammeter and
Voltmeter
1.5 Scientific Investigation
3.
4.
5. A derived quantity is a Physics
quantity that is not a base
quantity. It is the quantities
which derived from the base
quantities through multiplying
and/or dividing them.
7. Prefixes are the preceding factor used to represent very small and
very large physical quantities in SI units.
8. Scientific notation (also known as
Standard index notation) is a convenient
way to write very small or large numbers.
In this notation, numbers are separated
into two parts, a real number with an
absolute value between 1 and 10 and an
order of magnitude value written as a
power of 10.
Physical quantities that are very big or very
small need to be written in the standard
form so that it is neat, simple and easy to
read.
9.
10. Scalar Vector
Has Magnitude only Has Magnitude and direction
Examples :
Examples : distance, speed, mass, volume, temperature, density
displacement, velocity, acceleration, force, momentum, and
and energy
magnetic field
* Magnitude is the numerical value of a quantity.
11. difference between the actual value of a
quantity and the value obtained in
measurement.
Systematic Error
Random Error
Systematic errors are
errors which tend to 1. Random errors arise
shift all measurements from unknown and
in a systematic way so unpredictable
their mean value is variations in
displaced. Systematic condition.
errors can be 2. Random errors are
compensated if the caused by factors
errors are known. that are beyond the
control of the
observers.
12. Precision Accuracy
ability of an
instrument in
measuring a the approximation
quantity in a of the
measurement to
consistent
the actual value
manner with only for a certain
a small relative quantity of
deviation Physics.
between
readings.
13. The difference between precision and accuracy can be shown by the spread
of shooting of a tar-get (as shown in Diagram below).
Sensitivity
1. The sensitivity of an
instrument is its ability to
detect small changes in
the quantity that is being
measured.
2. Thus, a sensitive
instrument can quickly
detect a small change in
measurement.
3. Measuring instruments that
have smaller scale parts are
more sensitive.
14. Vernier Caliper
-The vernier caliper is
used in length
measurements to gain
an additional digit of
accuracy compared to
a simple ruler.
Click on the box to see the video…
16. Micrometer Screw Gauge
Range and
Accuracy
-The range of a
micrometer is
0-25mm.
- The accuracy
of micrometer
is up to
0.01mm.
17. Here’s a guide on how to use the micrometer…
• Turn the thimble until the
object is gripped gently
between the anvil and
spindle.
How to Use • Turn the ratchet knob until a
"click" sound is heard. This is
Micrometer? to prevent exerting too
much pressure on the object
measured.
• Take the reading.
18. Reading = Reading of main scale + Reading of
thimble scale.
Precaution
1. The spindle and anvil are cleaned with a tissue
or cloth, so that any dirt present will not be
measured.
2. The thimble must be tightened until the first
click is heard.
3. The zero error is recorded.
20. Ruler, Thermometer, Stopwatch, Ammeter and Voltmeter
• Thermometers of
range -10oC -
• A metre rule 110oC with
has sensitivity accuracy 1oC.
or accuracy • Thermometers of
accuracy of range 0oC - 360oC
1mm. with accuracy
2oC.
Thermometer
Ruler
21. •Ammeters are measuring
•analogue stopwatches of instrument used to measure
electric current.
sensitivity 0.1s or 0.2s
•Voltmeters are measuring
•digital stopwatches of instrument used to measure
sensitivity 0.01s. potential difference
(voltage).
Stopwatch Ammeter and
Voltmeter
Animated
Stopwatch
22. A report of the investigation must include:
-Objective of the experiment
-Inference
-Hypothesis
-Three types of variables: manipulated variable
-responding variable and fixed variable
-Defined operational variables
-List of apparatus
-Procedure
-Tabulation of data
-Analysis of data
-Conclusion
