Denise Lim's Pre-reading

Pre-reading for Project 3A

For this project, students are required to perform a simple experiment involving the rolling of a metal ball bearing down an inclined plane and measuring the time it takes to travel the horizontal track. To do this, students have to determine the angle of inclination for which the time of travel across the horizontal track will be least. Throughout the project, students have to make use of the concept of conservation of energy and use a stopwatch and photogate sensors in their data acquisition.

However, before proceeding on with the project, it is important to have some background knowledge about the concepts used in the project. These are the research that I have done:

What is a vector?

Vector is a quantity that has both magnitude and direction. It is usually represented by an arrow whose direction is the same as that of the quantity and whose length is proportional to the quantity’s magnitude. Although a vector has magnitude and direction, it does not have position. This means that as long as its length does not change, a vector is not altered if it is displaced parallel to itself. Some examples of vector are velocity and acceleration.

Vectors have certain rules of combination of which one is vector addition. As shown below, the vector sum can be seen by placing the tail of vector B at the head of vector A and drawing vector C which starts from the tail of A and ends at the head of B such that it makes a triangle. If A, B, and C are vectors, it must be possible to perform the same operation (commutative law) and achieve the same result (C) in reverse order, B + A = C.

Taken from project manual 3A

Other rules of vector manipulation include subtraction, multiplication by a scalar, scalar multiplication, vector multiplication and differentiation.