We measured the certain length we required the nichrome wire to be by using the ruler. I therefore decided to use a wire of a higher resistance; constantan, because it will allow me to get more reliable and comparable results. Our error bars could have begun to grow as the length of the wire lengthened because of its temperature. Do you know why doesn't the car analogy works fine? I will also ensure that there is a clear indication that the power is isolated by means of a switch and an L. .
The increase in collisions would mean an increase in resistance. The energy that the electrons is converted into light energy by the bulbs. Plastic is an example of an insulator. This quote from the Wiki page on explains reasonably well: In metals - A metal consists of a lattice of atoms, each with an outer shell of electrons which freely dissociate from their parent atoms and travel through the lattice. We recorded results of resistance for 2 different lengths which were 10cm and 20cm we did the experiment twice for each piece of wire. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 on this site the. We learnt that generally as the length doubled, so too did the resistance of the nichrome wire, proving our prediction was correct and accurate.
However, if our experiment had been accurate enough, at 40cm the resistance should have been 9 ohms. Of those shown below, the first four will be examined as part of this investigation. Double the cross section, half the resistance. I will not go above 1m or below 0. How the Length of a Wire Affects Its Resistance In my physics coursework I am going to investigate the effect of the length of a wire on its resistance.
This experiment has two sections which have to be carried out in order to get the correct results: Preliminary work: Find out which wire is the best insulator? Can you think of a way you could measure, or quantify, the brightness? Different cells provide electrons with different amounts of energy, or have greater 'voltage. Introduction: This first report in Physics will show the investigation of how the length of a wire affects its resistance. Electrons in a current electricity can make a magnetic field. Preliminary Results: Length Copper Iron Constantan Nichrome 10cm 1 0. Copper is an example of a conductor. Next, I will set the power pack on the lowest voltage possible to ensure that the current passing through the circuit isn't too high which could potentially affect the results because the wire would get too hot. If the length of the wire is increased the cross section of wire also have be increased accordingly to check the increase in the resistance.
This law is the basis of my first graph. Our error bars could have begun to grow as the length of the wire lengthened because of its temperature. Therefore, a thinner piece of wire will create more resistance because there is less space for the electrons to get though. This is because the free electrons in the wire bump into more atoms, thereby making it harder for electricity to flow. We have predicted that the longer the length of the wire the greater the resistance will be, we have predicted this because of our theory of resistors in series.
How Does The Diameter Of Wire Affect The Resistance In A Circuit? As a result, the resistance is lower in larger cross-section conductors. Cut each 8 inches long. I also think that the length of the wire and the resistance may be proportional and that if the length of the wire doubles, the resistance will also double. It acts as an electric pump. A water analogy is better - the pipe is always full of water, and for the same pump battery , the pressure voltage is always lower the wider the pipe, which equates to more flow and a lower resistance.
Furthermore, if you double the length of the wire, the resistance is roughly doubled. To help me plan my investigation I have completed a preliminary experiment in which I investigated the effect of the thickness of a wire on its resistance, using three constantan wires and one copper wire. My repeated readings were also all very similar and close to each other. A circuit consists of a bulb, a battery and a resistor. I'm using strands because it helps you see how a thicker wire is the same as having multiple smaller wires. How could that make the resistance go down? Now if you increase the length of this wire to 20 cm its resistance R will be twice than it was at 10 cm. The highway has to be designed to meet the specifications for both speed and volume.
I will place one crocodile clip at 0cm on the wire and the other at 5cm to complete the circuit. Now imagine counting the number of electrons passing this line, through the circle that is the cross section of the wire. Each resistor is able to conduct a certain amount of current. The electron flow will adjust itself to whatever the wire thickness is. For starters I will go through the main definitions, to get a better knowledge of what is going to happen. High quality copper cables can carry electrons quite far without much loss in the flow rate, but they are more expensive materials.
I predicted that as the length would be proportional to the resistance. When the water turned on pressure applied at the faucet, the pressure travels through the hose much faster than any particular water molecule, and water begins flowing out of the far end nearly immediately. The electrons colliding simply means more zig-zagging, not reduced speed. Halving the thickness of a wire does not double the resistance. If each strand has a certain conductance, having a wire with 20 strands means that your conductance is now 20 times larger than the wire with only 1 strand. This means they have more chance of colliding, which will make it harder for the current to flow. The free electrons bounce around, occasionally being impeded see below with the potential difference causing an average inclination to the direction of current.
Similarly, the shorter the wire, the smaller the resistance because there will be fewer atoms for the electrons to bump into, thereby easing the flow of electricity. As the electrons give off more energy, the atoms vibrate more, making it harder to allow the electrons to get through the wire. The circuit should be set up as in the circuit diagram below. Electron to electron collision is also one of the reasons of resistances. So only length is not important cross section of the wire is also an important factor. For the first set of data points, drag the micrometer tab to rest on 10 centimeters have the same person press down on the wire for every data point using the.