• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3

An Investigation into the relationship between the forces applied to a length of wire and its extension.

Extracts from this document...

Introduction

Physics Coursework An Investigation into the relationship between the forces applied to a length of wire and its extension. Aim: - To investigate the relationship between the extension [e] of a length of copper wire and the force [f] applied to the wire, to do this I intend to use Hooks law the linear modulus is known as stress/strain, also known as Young's modulus [E]. I hypothesise tat as we increase the amount of force applied to the wire, so its extension will increase. As this was what I found in previous experiments involving Hooks law. Diagram: - I will use Young's modulus as it links the two factors that we wish to investigate in that to find a value for Youngs modulus you need to find two values, stress and strain E = Stress where; - stress = Force [f] also;- Strain = extension [e] Strain Cross sectional area [a] original length [l] As we can see from above stress is calculated using force and cross sectional area there for involving force as we require, this will be my input variable and will be the value subject to change. ...read more.

Middle

i predict that the relationship between the two will be proportional. I have decided upon this outcome due to my background reaserch into the matter. I found that when streching metals a modulus applies called youngs modulus, this tells us that when streching a wire we get a graph of stress against strain where stress is equall to load/crossectional area therefore incorporating load and strain is equal to extension/original length. Advanced Physics by tom duncan states that tensile strain is directly proportional to tensile stress during elastic deformation. This statment is known as hookes law The outcome graph looks like this:- we can see a proportional relationship between the two variables at the beggining of the graph due to the constant gradient, a6t piont b we can see the graident is constantly changing. here youngs modulus no longer applies because the material has passed its elastic limit. i think that me graph of oad/extension will be very simular provided the other factors involved remain constant, these are cross sectional area and original length. To do this i intend to take multiple readings of the crosssectional area of the wire throughout the experiment to find an avrage as i know that the wire will become thinner as i strech it, as i descoverd in my preliminary tests. ...read more.

Conclusion

these allowed an exterrmly accurate measurement as small as 0.25mm and allowed us to measue lenghts as large as 10cm this was far larger than the required amount. To carry out the experiment i would use the apparatus in a way shwn in the above diagram (fig 1). this method was the best for me to use as it was implamentable as we had all the required equipment to hand, Although i did find some other methods in my research that would provide a more accurate set of results. i found it to be more accurate because the experiment was suspended from the celing and the wire was entrly vertical. unfortunatly this method was unimplamentable due to lack of equipment, i found the main reason why my method was less accurate was because the force was applied by the weight to the wire in a vertical irection but the majoraty of the wire ran horizontaly along the desk therefore the force as not properly tranfered through all the wire this was shown in my perliminary results because we set up another pointer near the weight and measued extension here it showed that the extension was far greater near the weight than near the clamp where we were measuring it. i also found that other factors infuencing my results were 'necking and creeping' Results:- ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Electricity and Magnetism section.

Found what you're looking for?

• Start learning 29% faster today
• 150,000+ documents available
• Just £6.99 a month

Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

Related GCSE Electricity and Magnetism essays

1. Investigate young's modulus behind Constantan and Copper.

4 star(s)

the metre stick, I would mark off using the marker the initial point so from when I add the weights I can see the increase in the extensions and finally when it completely breaks I will mark beside the metre ruler and thus work out young's modulus.

2. Draw stress and strain graphs for the metal copper and the alloy constantan. Calculate ...

4 star(s)

Figure four shows how alloys and pure metals differ. As can be seen alloy metals have a higher yield stress than pure metals, this is due to their structure makes slipping more difficult. Figure 4 Apparatus: * Table: To conduct experiment on * Wooden Blocks: Helps to keep wire steady and in place when fixed onto the G-clamp *

1. Investigating the young modulus of a wire

3 star(s)

Make sure you check that the fixed "G" clamp on the other side of the table is straight towards the pulley. 3. Extend wire from the "G" clamp over the pulley making sure that it is at least 10 cm below the pulley to use for hanging the weights on.

2. To plan an experiment to measure the extension in a piece of copper wire, ...

Below is a stress/strain graph for a ductile material, like copper. * The tension force acts on the wire when it is under stress and strain, it is equal and opposite which, when applied to the ends of an object, such as a wire, increase the length.

1. The elasticity of copper investigation

wire length and the changes * Level horizontal table: so it doesn't affect the experiment by adding more force to the load * Sellotape: make a pointer to see the change in wire size * Smooth pulley with clamp: so no friction can affect the force, F = �R *

2. Find out if the motion of an elastic band changes, by the rate of ...

Hence the meter stick is in the exact same position as previously when I come to use it again the next day in my lesson. Equipment/Apparatus: Below is a list of apparatus I will use during my preliminary series of experiments.

1. I will determine the extension of a piece of copper wire when various loads ...

[1] wooden block [2] G-clamp [1] white label sticker [1] clamp-on pulley [1] micrometer screw gauge [1] metre rule [2] rubber tile [1] protective goggle [1 for each mem.] Accuracy levels of equiptment Apparatus Accuracy/ + - mm Micrometer 0.01 Scale 0.1 Meter rule 1 Apparatus Accuracy/ + - kg-3

2. Physics Coursework Gravity Investigation

The release of the ball at a height of 40cm was repeated a second time giving three bounce height readings for a release height of 40cm. 7. The ball was released at four more different heights of 80cm, 120cm, 160cm and 200cm.

• Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to