Group 10-Time and Speed (Group members-,Nizha Arunasalam,Sheryl Wee,Glenda Tan ,Nicole Rolph

Time and speed.
What is Time?
Time is a duration of an event.

The SI unit which is second (s), is used to measure time.Other units are, milliseconds,minutes,hours,days,months and years.

When we measure time we use-

1) Clock

2)Stopwatch

3)Watches
4)stopclock

The stopwatch is a great example of an accurate measurement. We can either use the electronic or mechanical one.

Using the mechanical stopwatch only takes two steps.
1)You just have to press the start/stopbutton to start the stopwatch and press it again to stop the timing.

2)You can also press the reset button to of course reset the timing .

Unlike the mechanical stopwatch the electronic stopwatch can also record the time interval in hours. To take readings we can simply read off the digital display.

To use the electronic stopwatch we have to

1)Press the Start/Stop button to start the stopwatch and again to stop the timing.

2) Reset the stopwatch by pressing the reset button.
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Speed.

-Speed is the rate in which a distance is covered over an amount of time.

The S.I Unit for speed is metre per second(m/s).

Other Common units of speed are:-

1) centimetre per second(cm/s)
2) kilometre per hour(km/h)

3) miles per hour (mph)
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Because speed may vary over the duration of the journey,we use average speed to simplify calculation

To find the average speed we divide the total distance over the total time.

Average speed= total distance__
                          Total time taken

The instruments used to measure speed are:-

1) Speedometer (in all cars)

2) Anemometer (the speed for wind)

Hope you have learnt more about speed and time.

Thank you!~
By the members of Group 10, Nizha, Sheryl, Glenda and Nicole.