[填空题]
1.A student investigwy8z loma //wq x8+5+gd.dntjates the var w*8:nowlnv 7ciation of gas pressure with volume at a constant temperature. Air is trapped inside a gas syringe with a constant cross sectional area of A The plunger of the gas syringe is ow w:c nvn*87ltied to a mass holder. The student measures the volume Vof the trapped gas for different hanging masses with the external constant air pressure,$P_A$ remaining constant.
1.After each increase in mass, the student waits for some time to measure the volume of the gas. Outline why this is necessary.
The recorded data is plotted on a graph:
2.Draw the line of best fit for the plotted data.
3.Determine the gradient of the graph. $\times10^{-3}cm^3g^{-1}$
2.Theory suggests that
$(P_A-\frac{mg}{A})$V=k
where m is the total mass of the plunger and hanging masses, g is the acceleration of free fall and k is a constant.
1.Determine the unit of k in SI base units.
2.Calculate the percentage uncertainty of the volume V when the mass m is 700 g. %
3.In a particular experiment, the researcher measures
m=0.700±0.005 kg,
A=$0.00010\pm0.00001\:m^2$and
g=$9.81\pm0.01\ ms^{-2}$
Calculate the absolute uncertainty of $\frac{mg}{A}$.
