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\textbf{Names}  Hamish Huggard  Neelam Hari  Alex Smith  Anna Radionova  \textbf{Practical Set-up Notes and Lab-Specific Advice}  Section 3 seems to involve significantly more work than sections 1 and 2, so the best way of dividing up time would probably be  \begin{itemize}  \item 45 minutes for section 1  \item 45 minutes for section 2  \item 90 minutes for section 3  \end{itemize}  As the previous year’s summary notes, it’s better to mark each section as you go. It might also be advisable to give a demonstration of how to quickly determine means, standard deviations and standard errors using graphical calculators.  \textbf{Practice Problem - Approach and Solutions}  \begin{enumerate}  \item{Errors are differences between the measured value and the real value of a property due to systematic (miscalibration/bias) issues or random (gaussian) fluctuations. Uncertainties come from lack of resolution in the scale of the equipment being used, or our own ability to measure. Don't discuss human errors, as it's too general to be useful, and if you're following the correct experimental procedure then other (more important!) sources of uncertainty should dominate.}  \item{Add values, add uncertainties:  \begin{align*}  \text{Sum} &= \sum_{i=1}^N{x_i} \pm \sum_{i=1}^N{\delta x_i}\\  &= (102.3+44.8+5.67) \pm (0.2+0.2+0.08)\\  &= 152.77 \pm 0.48\\  &= 152.8 \pm 0.5 \text{cm}  \end{align*}  }  \item{Multiply values to find distance, add relative uncertainties, multiply relative uncertainty by distance to get absolute uncertainty.  \begin{align*}  \text{Distance} &= v\times t\\  &= 50\times1.2  &= 60  \delta(\text{Distance}) &= D(\frac{3}{50}+\frac{0.1}{1.2})\\  &= 60(\frac{3.6+5}{60})\\  &= 8.6\\  \text{Therefore, Distance} &= 60\pm8.6 \text{km}\\  &= 60\pm9 \text{km}  \end{align*}  }  \end{enumerate}  \textbf{Sample Data and Expected Results}  Based on data from Reserve Bank Coinage Specifications[1], the densities for 10 cent, 20 cent, 50 cent, 1 dollar and 2 dollar coins should come out as 6328, 6901, 6113, 7027, 6715 kg/m3 respectively. So values should roughly fall within 6000-7000 kg/m3. Note: I did measurements with the coins myself on Thursday. Diameters and masses are pretty consistent between testing one coin and five coins, but thickness isn’t - it’s very dependant on exactly where you test it. Students will probably need to measure the thickness of the coin at the *rim* to get a density in the range above. I took thicknesses from the center of each coin, and the calculated densities were closer to 7500kg/m3 - Alex. For the last question of part 1, the key thing for students to realise is that if 10 coins were used then each relative uncertainty would decrease by a factor of 10, which would ultimately propagate to 10 times the precision. Writing out the whole derivation would probably take too long, so I wouldn’t be picky about that.  \textbf{Key Discussion Points}  Section 1.3 - Archimedean method of determining volume by placing the coin in water and measuring the volume of displaced water would be good example.  Section 5.1 - Students should use |μ1 - μ2|/σ formula  Section 5.2 - Ideally students should give a rough probability of difference occurring due to random error using the table from A.5.3  Section 5.3 - Firstly, students should distinguish between measuring their own reaction, and the average reaction time. Secondly, students should realise that their experiment cannot prove or disprove the reference value, only give evidence in support of or against it. Thirdly, students should realise that taking everyone’s value in the class would introduce sampling bias.  \textbf{References}  [1] Retreived from http://www.rbnz.govt.nz/notes-and-coins/coins/new-zealand-coinage-specifications on 25th February 2016