[填空题]
1.The circuit shown iaz w:e ya0i4s;6m - (yi)p )fgjqwcv6ms used to me n3xl+z/ps6qm)ha9 7+ hwlwf easure the variation of the resistance R of a wire with the length L of the wire. The wirf /m7xw h9lq wa6nl+z+e 3hps)e is connected across points
$X$ and $Y$.
A voltmeter and an ammeter are connected to the circuit in order to investigate the relationship.
1.Draw the ammeter and voltmeter on the given circuit with their correct connections.
2.State the purpose of connecting a resistor in series with the wire as shown in the diagram.
2.The diameter d of the wire is kept constant at $d=0.58\pm0.01mm$ Determine the percentage uncertainty of the cross sectional area A of the wire. %
3.The graph shows the variation of resistance of the wire R with the wire's length L.
1.Draw the line of best fit.
2.Use the graph to estimate the resistivity of the wire. $\Omega$m
