Procedure Background — Solids Metals are good conductors. Plastics, wood products, ceramics and glass are insulators.
For that, the simple approach is to make the wires as long and thin as you can in order to maximize resistance. That said, another thing you can do is improve the precision of your measurements, e.
All About Circuits vol. Note that, while the circuit shown above includes a separate voltmeter and ammeter, you could also replace the ammeter with a shunt resistor with a known resistance and measure the voltage across it, as in the circuits shown at the bottom of the page linked above.
This would allow you to do the measurement using only a single voltmeter. As a bonus, the shunt resistor would also serve to limit the current across the circuit.
Never connect a voltage source, such as a battery or a simple lab power supply, directly across a low-resistance wire. This will create a short circuit, potentially causing the wire or the power supply to overheat. Instead, always include an appropriately sized resistor in series with the power supply to keep the current down to a reasonable level.
For an even more accurate resistance measurement, you could set up a bridge circuitlike the basic Wheatstone bridge shown here: In particular, for measuring low resistances, you might want to look at the Kelvin Double Bridge circuit described further down the linked page.Nov 09, · Resistivity: Is Copper the Best Metal Conductor?
( ratings) Problem: Observe the resistivity of different materials and material thicknesses and calculate electric conductivity. So is copper the best metal conductor? Copper is a better conductor than iron, which means current can flow easier (with less resistance) 4/5().
Summary Students build their own simple conductivity tester and explore whether given solid materials and solutions of liquids are good conductors of electricity. have students use the Will It Conduct? Worksheet to record their observations and answer questions.
Post-Activity Assessment Have students conduct research on the use of. Selection of reels of different wires (e.g. copper, Eureka, iron) of same gauge (e.g.
34 SWG). Procedure a Connect up a series circuit of two cells, and the ammeter, with a 30 cm length of one of the wires closing a gap between two crocodile clips.
Wires of different materials are suspended in distilled water and salt water. If the five wires aren't already cut, cut them into 6-inch lengths.
Using the pen or . Such wires of different materials do have different resistances (as objects). The difference in resistance due to the material is called the resistivity ('rho') of the material.
(Resistivity refers to the material, resistance to the object). The Resistance R is the resistance wire (constantan nichrorome) that you will be trying to calculate. Set the power supply to 1V. This limits the current through the wire in order to reduce any heating effect which may change the resistivity.