Do you think it is possible to make yourself louder without raising your voice? One way of doing it would be to use a megaphone or microphone, which turns your voice into an electrical signal and then back into a louder sound by using a speaker. However, what did people use before we had electrical amplification? In this experiment you can make a basic model of a megaphone without using electrical equipment!
Always remember to ask your parent or guardian to help you.
For this you will need the following:
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- Large piece of card/paper, the bigger the better.
- Piece of string slightly longer than your piece of paper.
- Scissors
- Pen/pencil
- Ruler
- Tape
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Step 1
Draw a line down the centre of your piece of card/paper.
Then take your pen/pencil and tie it round the end of the piece of sting.
Hold the string with one finger at the bottom of your card/paper and stretch the end with the pen/pencil out until the string is tight. |
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Step 2
Then you want to keep the string taught and draw a curve at the top of the paper as shown in the picture. |
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Step 3
Next you want to keep the string taught and at length but bring it towards you so that you use it to make the same shaped curve at the bottom of the page,
this is going to be the mouth piece. |
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Step 4
Connect the 2 curves with lines then use the scissors to cut it out then roll the cone together and fix it in place with tape. |
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Step 5
Now test it out by asking a friend to listen to you talk with and without using the mega phone. Does it make you louder??? |
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What is happening when you talk?
As you speak your voice box in your throat moves and creates vibrations.
It is this vibration that our ears pick up in the form of sound waves.
The voice box causes the air in our mouths and throat to vibrate, but when we use the mega phone there is a far larger volume of air to move and therefore makes a larger sound wave for our ears to pick up. Try it with different sizes of cones and see if it makes a difference.
