# Investigating the induced emf with the number of windings and different heights

Investigating the induced emf by changing the number of windings

Introduction and design

This investigation is based on Faraday’s experiments on electromagnetic induction. What we want to investigate is to see if there are any connections between the number of windings and the induced emf. In Faraday’s experiment, he concluded that a changing magnetic field can induce an emf.

A hypothesis is that the coils of wire have a constant magnetic field. If we than increase the coils then we will get a stronger magnetic field. So, if we double the number of windings on the coil, we should get a magnetic field with a strength doubled. So the induced current and emf should also be doubled with a doubled magnetic field. Also, the height will influence the change in magnetic flux when it enter the fields and the proposal would be an increase in height will increase the emf

So the research question would be: “investigating the induced emf in with the number of windings  and different heights”

The variables in this experiment are height, acceleration, voltage (emf), current, time and magnetic field.

• The dependent variables are the time, voltage (emf) and current.

Current and voltage is proportional when it enters and changes the magnetic field and the time is dependent of the height.

• The independent variables are the magnetic field and height

We can manipulate the strength of the magnetic field by using different coils of windings. We will also try to change the height.

• The controlled variables is the acceleration

The acceleration is gravity and is a constant according to Newton’s law of gravity.

The equipments we will use are:

• Three coils with different windings
• A magnet
• A ruler
• A stand
• A data logging program with equipments

The variables and equipments are identified and we will develop a method to collect data.

Since the induced emf and current is proportional to each other, we can choose to investigate the induced emf. However, we got two independent variables, which mean we have to do the experiment twice and change the ...