This document discusses scalar and vector quantities. It provides examples of a scalar quantity as a girl walking 4 meters, which only has a magnitude, and a vector quantity as a girl walking 4 meters east, which has both a magnitude and direction. A scalar quantity only has magnitude, while a vector quantity has both magnitude and direction.

1. 1.3 : :Scalar Quantities and Vector Quantities
1.3 Scalar Quantities and Vector Quantities
1. Some physical quantities are used to
describe the motion of objects.
2. These quantities can be divided into
two categories :
a) Scalar quantity
b) Vector quantity
i. Scalar quantity
A girl walks 4 meters.
Magnitude : _________
Direction :__________
ii. Vector quantity
A girl walks 4 meters East.
Magnitude : _________
Direction : __________

2. i. Scalar quantity
A girl walks 4 meters.
Magnitude : 4 meters
Direction : No direction
A scalar quantity is
a physical quantity
which has magnitude
only
ii. Vector quantity
A girl walks 4 meters East.
Magnitude : 4 meters
Direction : East
A vector quantity is a
physical quantity which
has both magnitude and
direction.

3. Do the exercise on Science
Process Skill page 5

4. 1.4 : MEASUREMENT
Measurement is the process of
determining the value of a
physical quantity using scientific
instruments
The length of an object
can be measured by using
a metre rule, vernier
callipers or micrometer
screw gauge.

13. 1.5 : ACCURACY, CONSISTENCY AND
SENSITIVITY
Accuracy in
measurement is the
degree of
closeness of a
measurement value
to the actual value
A measurement
with a smaller
percentage error
has a higher
accuracy
Consistency (precision)
is the degree of
uniformity or
reproducibility of the
measurements.

14. inaccurate but consistent
accurate but not consistent
consistent and accurate
inaccurate and not consistent

15. Sensitivity is the ability of an
instrument to detect small
changes in the physical
quantity being measured
A measuring instrument which has
smaller scale divisions is more
sensitive
A more sensitive measuring instrument is able to :
1. Detect very small changes in the physical quantity
that is being measured.
2. Respond more quickly towards changes in the
physical quantity that is being measured.

16. RANDOM ERRORS
Uncertainties in the
measurement due to:
1. Observer
(parallax error)
2. The surroundings
3. The instruments
Repeat measurements
(taking several readings)
and calculating the
average
SYSTEMATIC ERRORS
Uncertainties in the
measurement due to:
1. Observer
2. The surroundings
3. The instruments
(zero error)
Using different
instruments and taking
measurements carefully