Abasiono Bassey
PHYS 2125-0043
June 7, 2019
Experiment 2
Vector Addition

Objectives
1. Obtain the resultant of a number of forces acting on a body.
2. Obtain the resultant of the same forces by drawing a vector diagram to scale to find its
magnitude and direction.
3. Determine of the resultant using the analytical method, including the law of cosine for the
magnitude and the law of sine to find its direction in one instance. The components method
will also be used.
Materials
1. Force table
5. Strings for suspending the masses
2. Weight holders (4)
6. A ring
3. Pulleys (4)
7. A metal pin
4. Slotted weights
8. A protractor
9. Sheets of plain paper and graph paper
Introduction
A vector is a physical quantity that has both magnitude
and direction. Examples include force, weight,
displacement, velocity and acceleration. On the other
hand, a scalar is a physical quantity that has magnitude
only, examples speed, mass, distance, temperature,
population. A vector may be represented by a letter
example with a bar on top indicating the direction, or by a
bold letter, example
A
.
A vector
A
can be written
as a sum of two vectors
A
x
and
A
y
along the x and the y-axis respectively, as shown
.
A
x
and
A
y
are called
the components of vector
A
and are given by
:
A
x
= A
cosα
A
y
= A
sinα
α (≤ 90
0
)
is the angle vector
A
makes with the
x-axis.