Practical Investigation：Resistance in Wire
G10 science
By Freya Li
Practical Investigation
Resistance in Wire
Aim:
To investigate if the length of wire affects its resistance and find out how the resistance changes when the length of wire increases.
Hypothesis:
My prediction is that as the length of wire increases, the resistance will also increase. This is because current is the flow of electrons in a circuit and voltage makes the electrons flow through the circuit. The electrons have to collide with the atoms in the wire, which makes the electrons harder to flow through the circuit. And there are more collisions between electrons and atoms, as the length of wire increases. The higher resistance means more voltage is needed to push the current through the wire.
Variables:
1. Independent:
The length of wire will be changed in the circuit by moving the crocodile clips. (Length: 15cm, 25cm, 35cm, 45cm, 55cm)
2. Dependent:
I will calculate the resistance by measuring the voltage, current and using ohm’s law. (R=v/I) The voltage and current will be measured at least 3 times by using the voltmeter and ammeter.
3. Controlled:
Controlled variables
How will it be achieved
The diameter of the wire
Choose the wires with same diameter
The type of wire
Use the same type of wires
The temperature of wire
Avoid connecting the circuit for long time
Method:
Equipment:
1 m nichrome wire (diameter 0.46mm)
1 Ammeter
1 Voltmeter
Power Pack
5 wires leads
2 crocodile clips
Meter ruler
Procedures:
1. Connect the power pack to the main power supply by putting the plug in the socket and switch it on at the socket. Make sure the switch of the power pack is turned off.
2. The apparatus is set up as shown in the diagram below, with the ammeter connected in the series and the voltmeter connected in the parallel.
3. A nichrome wire is attached to both end of a meter ruler and then it is attached to the circuit with crocodile clips.
4. The crocodile clips will be moved to different lengths, from 15cm to 55cm, going up
By Freya Li
Practical Investigation
Resistance in Wire
Aim:
To investigate if the length of wire affects its resistance and find out how the resistance changes when the length of wire increases.
Hypothesis:
My prediction is that as the length of wire increases, the resistance will also increase. This is because current is the flow of electrons in a circuit and voltage makes the electrons flow through the circuit. The electrons have to collide with the atoms in the wire, which makes the electrons harder to flow through the circuit. And there are more collisions between electrons and atoms, as the length of wire increases. The higher resistance means more voltage is needed to push the current through the wire.
Variables:
1. Independent:
The length of wire will be changed in the circuit by moving the crocodile clips. (Length: 15cm, 25cm, 35cm, 45cm, 55cm)
2. Dependent:
I will calculate the resistance by measuring the voltage, current and using ohm’s law. (R=v/I) The voltage and current will be measured at least 3 times by using the voltmeter and ammeter.
3. Controlled:
Controlled variables
How will it be achieved
The diameter of the wire
Choose the wires with same diameter
The type of wire
Use the same type of wires
The temperature of wire
Avoid connecting the circuit for long time
Method:
Equipment:
1 m nichrome wire (diameter 0.46mm)
1 Ammeter
1 Voltmeter
Power Pack
5 wires leads
2 crocodile clips
Meter ruler
Procedures:
1. Connect the power pack to the main power supply by putting the plug in the socket and switch it on at the socket. Make sure the switch of the power pack is turned off.
2. The apparatus is set up as shown in the diagram below, with the ammeter connected in the series and the voltmeter connected in the parallel.
3. A nichrome wire is attached to both end of a meter ruler and then it is attached to the circuit with crocodile clips.
4. The crocodile clips will be moved to different lengths, from 15cm to 55cm, going up