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

Building a mass balance to measure small weights (0g-100g) using a rotary potentiometer

Extracts from this document...

Introduction

BUIDING A MASS BALANCE TO MEASURE SMALL WEIGHTS(0g-100g) USING A ROTARY POTENTIOMETER Introduction: Nowadays, we have mass balances, weighing scales etc to measure masses but we hardly have devices that measure small masses. Sometimes, we may have to measure objects with small masses say 10g to 100g and my model is created backed up with this idea. Components Used: Digital multi-meter, Meter rule, Retort Stand, Clamp, Rotary potentiometer, Power supply (5V), Spring, Masses (in unit of 10g), 2k and 3k resistors, 1k variable resistor, amplifier. Reason For Choice Of Components: * Rotary Potentiometer: I used a rotary potentiometer so that when masses are placed on the meter rule the change in voltage (output) could be noted. The rotary potentiometer is of 5k Ohms but I connected it to a 5V power supply as a more convenient way of measure. As the potentiometer moves the resistance changes and also does the voltage. * 2k, 3k Fixed Resistor and 1k Variable Resistor: I used these resistors in order to make a Wheatstone Bridge so that there will be a significant change in output when masses are added to the meter rule. * Amplifier: I am using the amplifier in order to make my model more sensitive and obtain a more accurate result. ...read more.

Middle

2) When readings were not been taken I ensured that the power supply was switched off. 3) When readings were not being taken, I removed masses from the meter rule in order not to make the spring distorted. 4) When I was not using the multi-meter, I turned it off in order not to run down the battery an give me an accurate result. The electrical cell used was one of a low voltage therefore my working condition was not that dangerous. Experiment: I Hung masses on the meter rule, then record the change in output from the multi-meter. I repeated the process two more times with different masses then found out the average of the readings for more accuracy in my result. I then used my average output to plot a graph. Observations In my initial experiment when masses were put on an inextensible string hanging from the meter rule I noticed that there was no change in the output reading from the digital multi-meter unless heavy masses are put and this system did not produce a sensitive setup this was when I got the idea of the Wheatstone Bridge. The Wheatstone Bridge did not give me a satisfactory result either! ...read more.

Conclusion

Basically this is what I expected i.e. an increase in mass would increase the output produced. From the graph we can determine the mass of object (approximately). To do this place the object on the model and read the output and read of the corresponding mass from the graph and this gives us the approximate mass. FITNESS FOR PURPOSE Resolution: Mass/g(10.00) Output/V +1.00 2.83 +2.00 2.86 Mass/g(30.00g) Output/V +1.00 3.34 +2.00 3.37 Basically, form the table above we can see that when 1.00g is added to known masses, the output is the same for the known mass which implies that 1.00g does not make a difference to the output reading. Moreover, when 2.00g is added to known masses say 10.00g or 30.00g the output changes. Therefore, the smallest change (resolution) my setup can detect is 2.00g. Sensitivity = Change In Output , Change In Input = 0.24 10.00 = 0.024V/g Response Time: This is the time it takes for the output to be detected by a sudden change in mass. In my model the change is almost immediate so the response time is quite fast. Although the last digit on the digital multi-meter fluctuates this only means that the change in magnitude is been resolved. Linearity: My graph (output against mass) is a straight line graph(upward sloping) showing the relationship is proportional(as mass increases, the output increases). ...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 Systems and Control 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

See related essaysSee related essays

Related GCSE Systems and Control essays

  1. Elecrtonics - Audio Amplifier

    I will now test it and I expect the voltmeter to show 9v when I/P 1 is active, 8v when I/P 2 is active and so on. These tests gave the results I was expecting. This sub system is working properly.

  2. Getting On Line Without a Computer or Internet Access at Home

    Hill PL; Chester Boro and Township (Joint Free Library of); Clark PL; Clementon Memorial; Cliffside Park PL; Clifton Free Public Library; Closter PL; Collingswood PL; Cranbury PL; Cranford Public Library; Cresskill PL; Crosswicks PL; Cumberland County Library D Delanco PL; Demarest PL; Denville Free PL; Deptford Township (James H.

  1. Solar Power

    Most of the country's solar generation would stand in the Southwest. The existing system of alternating-current power lines is not strong enough to carry power from these centers to consumers everywhere and would lose too much energy over long hauls.

  2. The paper discusses the issues associated with the risks assessed between the organizations bidding ...

    Implementation Plan The planned merger should be implemented by first identifying all of the variables and notifying the staff of the expected changes and company goals. The staff should although being made aware of all the changes that will be taking place within the organization should be reassured that although

  1. The aim of this investigation is to design, build and test a sensor.

    Do the same for 4.02 to 4.03 volts and 4.03 to 4.04 volts, repeating steps 2, 3 and 4 for both, making sure to move 50mm away the LDR from the light bulb each time 7. Take averages of the 3 distances the LDR moved for each distance away and

  2. Create a circuit that includes a sensor, which in turn will enable me to ...

    As I will be using a potential divider in my circuit, therefore I will require a fixed resistor as well as the rotary potentiometer. I will repeat my experiment 4 times overall, using 10k?, 22k?, 47k? and 100k? once each.

  1. Electronics… did it change the way we are living nowadays?

    In the present, almost all our appliances use electronics and we are enjoying its service but many of us don't know how it works. For most people, this is a big mystery, or some just choose to ignore it. We often take these things for granted.

  2. 'A small business wishes to sell a range of electronic games to help alleviate ...

    It is also very expensive. Softwoods such as pine Softwoods come from very fast growing trees and so are less expensive to produce and buy. They are generally very easy to cut and work with but must be finished to a high standard to have a viable amount of durability.

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