Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Solenoid Pracical Design

  1. Aug 4, 2008 #1
    Hey guys, I'm really having problems with this. Normally I get pretty good grades but this just has me completely stuck. It's hard because I have to design something, yet it doesn't seem like there's a lot of easily understanable information out there to draw from. Any help would be greatly appreciated.

    1. The problem statement, all variables and given/known data

    Plan a procedure to investigate the relation between the current in a solenoid and the magnetic field produced.

    Your documentation should show:

    -Evidence that you have considered possible ways of detecting the magnetic field
    -Evidence that you have considered a range of methods for measuring the magnitude of the magnetic interaction.
    -A clean, labelled diagram of your choses apperatus
    -A description and eplination of the measurments to be taken and the variables to be kept constant.
    -A description of the experimental procedure to be followed.
    -A suggested method of determining the relationship between the current in the solenoid and the magnetic field strength produced.

    2. Relevant equations


    3. The attempt at a solution

    Ways I have considered to detect the magnetic field:

    Bar magnet. You can use a bar magnet suspended on a string, move it around until it free to move and align to the magnetic field.

    Iron Filings.

    If iron filings are placed on a piece of paper above the solenoid then they will align themselves to the shape of the magnetic field lines around the current carrying solenoid. The closer the filings are together the stronger the magnetic field.


    You can detect the magnetic field with a compass around a solenoid, the compass needle will point to the earths magnetic field if there is no magnetic field present otherwise if there is a magnetic field present the compass needle to point towards the magnetic field of the solenoid.

    Force of bar magnet on scales.

    The three types of scales available for use are newtons force spring, triple beam balance and electronic scales. I have chosen electronic scales because that is easiest.

    The weight of the bar magnet will increase on the scales as the current is increased, therefore the magnetic field of the solenoid increases, therefore the force on the bar magnet is increased. This means it is a good way of measuring the magnetic field because there is an actual variable to be measures – the weight. We can see increases and decreases in this related to the force due to the current.

    Strength of compass orientation.

    Distance between metal filings. The closer the filings are together the stronger the magnetic force. Unfortunately this cannot be easily measured in a tangible way.

    Current – Independant variable
    Force on bar magnet – dependant variable
    Everything else is a constant.

    1. Attack a solenoid to a string, set up a retort stand with a clamp and connect the solenoid so it is suspended with its north pole facing down.
    2. Place a bar magnet on a set of electric scales with it’s north pole facing upwards. Place the scales and magnet under the suspended solenoid.
    3. Take note of the weight of the bar magnet or set the scales to zero.
    4. Connect the solenoid to the power and turn on the voltage. Measure the weight of the bar magnet when the force has been applied.

    As you can see I have some ideas but I am having trouble expanding it.

    Thanks :D
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted