Investigating Which Factors Affects the Resistance in a Circuit

Investigating Which Factors Affects the Resistance in a Circuit

Aim – To investigate which factors that will affect the resistance in

an circuit.

Factors – All these things might affect the aim

* Material the current passes through

* Temperature of wire

* Length of wire

* Thickness of wire

We will change the length and thickness of the wire each time, staring

with a set length then changing the thickness, and then starting with

a set thickness will we change the length. We will start with the wire

0.5mm then going up in 0.5mm stop at 3mm. Also the wire length will

start at 1cm and go up in centimetres.

Science – Resistance is the property of any many materials, which

affects the passage of an electrical current. A substance such as

copper is a good conductor of electricity; this means the electrons

can travel through it easily.

Poor conductors (insulators) such as rubber have a high resistance;

this means that it is difficult for electrons to pass through.

Resistance is measured in OHM.

In a material that is a good conductor of electricity, electrons move

round freely, when a difference of potential occurs, the electrons

more from positive to negative. (Whereas current moves from negative

to positive) If the material is changed, then so is the resistance as

different materials have different amounts of free moving electrons.

If the temperature is changed the free moving electrons move round in

all directions, causing then to not flow round the circuit so

smoothly.

If the length of the wire is changed the resistance will change

because the all the electrons have to travel further.

Method – The dimensions of the wire will be changed, the length and

the thickness. Two separate experiments will take place each one

testing the current with the length and the thickness as variables.

The volts will be kept at a relatively low voltage to stop the wire

burning out.