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

Situations in Everyday Life Where Monitoring and Measuring Devices are Used

Extracts from this document...


Situations in Everyday Life Where Monitoring and Measuring Devices are Used Computers are used to control the operation of many machines and everyday devices. The machine or device contains an embedded computer circuit board that processes input and sends signals out of the computer to switches and motors that make the machine in a particular way. The input is provided by devices called sensors. Sensors continually monitor and measure variables such as; light intensity, temperature, rotary motion, pressure, humidity, oxygen levels and sound intensity. Some examples of machines or systems that contain sensing devices are: 1. A washing machine. This is a very sophisticated machine that contains a collection of sensors such as; rotary motion sensors - to sense the speed of the spin dryer. Temperature sensor - to sense the temperature of the water for washing. A pressure sensor - to sense when water is in the machine and to prevent the door from opening when water is present. 2. A camera. This contains a selection of sensors that include; a light sensor - to sense when the lens is exposed or if a flash is needed. ...read more.


As the sulphur is produced it makes the solution cloudy. The usual way in which the rate of reaction is measured is by noting the time taken for enough sulphur to be produced to hide a dark cross on a piece of paper under the reaction container. This is taken as a measure of the speed of the reaction under the given conditions. Limitations of this Method: 1. If different people have to read the results, the accuracy of the results will vary as each person has a different level of eyesight. 2. It is hard to stand exactly the same distance away from the container each time you look to see when the cross has disappeared. 3. You cannot keep the temperature of the solution constant. Alternative to the Method: The availability of sensors has meant that it is possible to get improved results. Instead of measuring the time for the cross to hidden, it is possible to measure the light intensity passing through the mixture over the time of the reaction by using a light sensor. ...read more.


* At the start of the reaction (point A on the graph), the amount of light that passes through the reaction mixture is at it's maximum. * As the reaction continues, the amount of sulphur produced starts to increase and this makes the mixture cloudier and the amount of light that gets through to the sensor begins to get less (between points B and C). * As the reaction continues it starts to slow down as the reactants get used up and no more sulphur is produced. At point D the reaction is effectively over and the amount of light reaching the sensor stays at a constant value. The graph produced by the INSIGHT2 software is a bit limited: * It is difficult to calculate values since it does not produce gridlines of sufficient accuracy * The Datalogger sometimes produces 'odd' results (like dropping to 0 output for no reason) * It is possible to produce trend lines and the equation of the trend line can be calculated by the software To get over the problems above, I saved the data as a CSV file that I then exported to a spreadsheet application (EXCEL). Printout of the graph (from EXCEL) produced: ...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 Patterns of Behaviour 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
  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work