You use a stopwatch to take repeated measurements of the time it takes a ball, from rest, to roll a fixed distance down a slope.  As your best estimate of the time the ball actually takes to roll this distance you should:

The world record for the 100m sprint, held by Usain Bolt, is 9.58 seconds.

With this information alone, i.e. without using extra information about the accuracy of Olympic sprint track timing and distances, which of the following is the correct statement about his average speed and its uncertainty?

Hint I: The average speed can be calculated from v = d/t.

Hint II: For given data where no other uncertainty information is provided, a reasonable estimate of the uncertainty will generally be:

            ½ (last significant figure)

This means that you should take the distance to be d = 100.0 ± 0.5 m and the time to be t = 9.580 ± 0.005 s.

Hint III: Refer to the section on combining uncertainties in the Guide to Experimental Work.

The following data is recorded for the oscillation period of a pendulum

The average value is 5.29 s, what is the absolute uncertainty in seconds? For the purpose of this quiz, do not include the unit in your answer, just the numerical value.

Hint: you might find it useful to open an Excel spreadsheet to answer this.

In your physics experiments, when you take a single measurement using a ruler, a digital thermometer or other such measuring device (for which you do not have the manufacturers specification of uncertainty) you should take the uncertainty to be:

You are recording counts from a Geiger counter to measure small amounts of ionizing radiation from some samples. Whilst performing the measurement of the last sample, you get hungry and fetch and eat your lunch banana. After you finish and pack everything away, your colleague sees your banana skin. Firstly they are shocked and appalled that you would eat in a radioactive lab, this is very dangerous! But worse, bananas are mildly radioactive and its presence could have contaminated your final sample. What should you do?

If Alex's height is given as 143.9 ± 0.1 cm, which of the following statements accurately captures this?

Which of the following measurements of a length is the most precise?

If the measurement of a time period is stated as 12.5 ± 0.5 s then the percentage uncertainty in this measurement is: