GCSE Physics Resistance of a Wire
Before starting my coursework I have decided to chose a factor that will affect the resistance of a wire.
I shall do this by going through all of the factors that affect the resistance of a wire and how I would
measuring each factor to find out which would be the most effective and easiest factor to measure.
Below is a list of factors and reasons why they affect the resistance of a wire. From this list of factors I
shall only pick one factor to investigate. To explain the how the factors would affect the resistance of a
wire I have drawn a diagram to show how resistance occurs.
WIRE
ATOMS=
ELECTRONS=
Resistance occurs when the electrons travelling along the wire collide with the atoms of the wire.
These collisions slow down the flow of electrons causing resistance. Resistance is a measure of how
hard it is to move the electrons through the wire.
Factors
.Temperature : If the wire is heated up the atoms in the wire will start to vibrate because of their
increase in energy. This causes more collisions between the electrons and the atoms as
the atoms are moving into the path of the electrons. This increase in collisions means that
there will be an increase in resistance.
2.Material : The type of material will affect the amount of free electrons which are able to flow through
the wire. The number of electrons depends on the amount of electrons in the outer energy
shell of the atoms , so if there are more or larger atoms then there must be more electrons
available. If the material has a high number of atoms there will be high number of electrons
causing a lower resistance because of the increase in the number of electrons. Also if the
atoms in the material are closely packed then the electrons will have more frequent collisions
and the resistance will increase.
3.Wire length : If the length of the wire is increased then the resistance will also increase as the
electrons will have a longer distance to travel and so more collisions will occur. Due to this
the length increase should be proportional to the resistance increase.
4.Wire width : If the wires width is increased the resistance will decrease. This is because of the
increase in the space for the electrons to travel through. Due to this increased space between
the atoms there should be less collisions.
To chose which factor I am going to investigate I am going to consider how I would measure each
factor and which factor would be the best and easiest to record.
Before starting my coursework I have decided to chose a factor that will affect the resistance of a wire.
I shall do this by going through all of the factors that affect the resistance of a wire and how I would
measuring each factor to find out which would be the most effective and easiest factor to measure.
Below is a list of factors and reasons why they affect the resistance of a wire. From this list of factors I
shall only pick one factor to investigate. To explain the how the factors would affect the resistance of a
wire I have drawn a diagram to show how resistance occurs.
WIRE
ATOMS=
ELECTRONS=
Resistance occurs when the electrons travelling along the wire collide with the atoms of the wire.
These collisions slow down the flow of electrons causing resistance. Resistance is a measure of how
hard it is to move the electrons through the wire.
Factors
.Temperature : If the wire is heated up the atoms in the wire will start to vibrate because of their
increase in energy. This causes more collisions between the electrons and the atoms as
the atoms are moving into the path of the electrons. This increase in collisions means that
there will be an increase in resistance.
2.Material : The type of material will affect the amount of free electrons which are able to flow through
the wire. The number of electrons depends on the amount of electrons in the outer energy
shell of the atoms , so if there are more or larger atoms then there must be more electrons
available. If the material has a high number of atoms there will be high number of electrons
causing a lower resistance because of the increase in the number of electrons. Also if the
atoms in the material are closely packed then the electrons will have more frequent collisions
and the resistance will increase.
3.Wire length : If the length of the wire is increased then the resistance will also increase as the
electrons will have a longer distance to travel and so more collisions will occur. Due to this
the length increase should be proportional to the resistance increase.
4.Wire width : If the wires width is increased the resistance will decrease. This is because of the
increase in the space for the electrons to travel through. Due to this increased space between
the atoms there should be less collisions.
To chose which factor I am going to investigate I am going to consider how I would measure each
factor and which factor would be the best and easiest to record.