Question

I have a tube with glycerine. I drop small balls inside and I want the time of the ball's distance between 2 lines of the tube. Please suggest the most accurate and modern method to time that distance and the appropriate equipment. (to have the least errors)

Answer 1

• The instrument available for measuring the time of fall is the stopwatch. It can be either a mechanical type or a digital type.
• Before dropping the metal balls, make sure to wet the balls with the same liquid. here it is glycerine. Then drop the ball one by one gently into the cylinder using a spatula.
• Now make the starting point sufficiently below the surface of the liquid, so as to reduce your reaction. So that you can start the stop wat at the exact time the ball crosses the first mark. This will help reduce errors.
• If you are using a mechanical stopwatch make sure that before starting, the dial is at zero. If not record the error and after time measurement, subtract the recorder error from the measured value.
• Finally, for the same distance, make a number of time measurements, (say 5 or more measurements) and take the average. this will reduce the random error.
• And keep in mind that in any experiment there will be some sort of parallax or personal error, which can be reduced by more carefulness from the person taking the measurement.

Hope these tips help you. If you need any further clarification, comment in the comment box.