PHYSICS

Physics

Physics

Introduction

This experiment used the relationship amongst the load of deflection and beam to determine the elasticity of the beam by using Young's modulus. The experiment was undertaken on 3rd of November 2011. The time period was between 3pm to 5pm in the Knowledge Dock Building of the University of London at the laboratory which was followed by 2 people and then the guidelines are followed which are presented in Section 3.2. The main point of the study is to show that when the beam is 72.8cm in length, the deflection can occur in a decreasing and increasing height when a load is applied of 0.5 kg. The report consists of analysis, methods and results and also the apparatus which will be used before reaching to the conclusion and a brief discussion being presented. Young's modulus is further explained by contrasting the relationships between deflection and loads of elasticity.

Literature review

Aforementioned to the experiment, the literature review which was related to the understanding relationship between deflection and load was also taken into consideration and values were also extracted for Young's model. This was done to compare the results of the experiment.

Deflection

Deflection of the beam has been explained by Smith (2001, pg 217) as a lateral turn or bend which is the deviation movement for the pointer of the instrument from its initial point. Furthermore, this deflection is dependent upon many other factors which help to determine direction, amount and magnitude of the deflection. These factors are listed below:

The flexibility of the material used

The amount of restraint placed on the system by its support

Pattern of the load

The structure's geometry which includes flexural rigidity and shape of the member

Load

Smith (2001, pg 220) further makes a point by saying that “the deflected form of a structure will also be affected by the magnitude, direction and pattern of load applied to it. In other words, the patterns of load have a major influence on the deflected form of a structure.” The following figure represents the beam deflection when load is placed on it.

Simple Support

Figure 1: Beam deflection under the application of a load

The formula for the deflection of a load is shown by Gauld (1984, pg. 46 - 47):

Where W = load (m)

L = span (m)

E = young's modulus (N/m2)

= Second moment of area (m4)

But

Where b = cross-sectional width of beam

d = cross-sectional depth of beam

Figure 2: Diagram showing base, length and depth

Young's Modulus of Elasticity in terms of value is shown by Morgan (1978, pg 13):

E =

In the example, stress = 30 N/mm2 and strain 0.00015

Therefore E =

A change that takes place due to the load being applied to the vertical or horizontal beam and helps the beam to diminish is known as beam deflection. It also means that the pull and push must happen too. This also means that deflection is directly linked to the amount of load applied. The value extracted from Young's modulus can be contrasted with experiment's results.

Research Methodology

The procedures and apparatus used for the experiment ...