How to make a timer

[j_nes66]

The task is to build a device that can measure time in seconds. Its needs to measure at least 1:30 minutes. There will be pints given for creativity and accuracy. I need ideas and if possible, links to see the instructions on how to make it. (This is for Physics class)

[deleted-71417]

Hi,

One simple idea is to make a sand clock, one of the oldest known methods of measuring time:

http://www.wikihow.com/Make-a-Sand-Time ... ic-Bottles

http://www.ehow.com/how_4795565_sand-timer.html

http://www.dadcando.com/default_DOING.a ... xperiments

Anothre option is a water clock:

http://www.ehow.com/how_2086422_build-water-clock.html

http://physics.nist.gov/GenInt/Time/early.html

http://www.sciencenetlinks.com/lessons. ... 11&DocID=2

http://weatherill.ndo.co.uk/babygoz/fre ... /water.pdf

You could also build an electronic clock:

http://electronics.howstuffworks.com/ga ... -clock.htm

There are some HeathKit clock plans on this site:

http://www.vintage-radio.info/heathkit/

This may help build a digital clock:

http://www.ehow.com/how_4893964_digital-clock.html

There are lots other ways to build a clock, including mechanical escapement systems and pendulum systems. The point of your school assignment is for you to research these and make your own choice.
This should be an interesting and challenging assignment. Good luck!