Scalar and Vector

2. Discussant: Teacher Cherry

3. Objectives:
At the end of the lesson you will be
able to:
• Differentiate quantities in terms of
magnitude and direction;
• Use graphical and mathematical
methods of achieving the resultant
of vectors.

4. Scalar Quantity
Is a quantity that can be completely described by
a magnitude only, that is, simply a numerical
value and a unit.

5. Vector Quantity
Is a quantity that needs both magnitude and direction to
completely describe it.
50km north

7. •Vector give more information
than scalars due to direction.
•If in scalar, if your mass is 50kg,
it will remain 50kg even if you
face east or west or go far
beyond earth.
•Your body temperature does not
change even if you are standing
or lying down.

8. Scalars
Symbol Name Example
d Distance 50m
s Speed 60kph
t Time 20s
E Energy 2,000 J
Vectors
Symbol Name Example
d Displacement 50m North
v Velocity 60 kph West
F Force 100 N up
a Acceleration 5 m/s2 down

9. Categorize each quantity as being either a
vector or a scalar
1. 37⁰ C
2. 100 kph
3. 20 m/s North
4. 5km Southeast
5. 4,000 calories

10. Vector Representation
A vector is represented by a boldface,
that is, A or v.
Graphically, vectors are represented by
an arrow.
The length of the arrow represents the
magnitude of the vector while the
direction of the arrow represents the
direction of the vector.

11. Example 1: A displacement of 100 km to the East

12. Example 2: A force of 30N up

13. Example 3: A velocity of 60kph Northwest

14. Mathematical method
10m + 10m = 20m 
10km + -10km  = 0
10m  + 20m  = 30m 
10km + -20km  = -10km 
20m + -10m = 10m

15. Pythagorean Theorem
Is used for determining the
resultant of two vectors that
make a right angle of each
other.
This means that this method
cannot be applied in adding
more than two vectors that are
not at 90 degrees to each
other.

16. • Note
• c is the longest side of the triangle
• a and b are the other two sides

17. A man leaves his house and walks 8 km North then proceeded 6 km
West. Determine the man’s final displacement.