Question 37
You are going to investigate how sound is reflected.
Work in groups of two or three.
You will need:
- 2 plastic or cardboard tubes and a mobile phone, a large sheet of paper, or 2 A4 sheets taped together, a block or piece of hard plastic, metal or a tile for a reflecting surface, piece of wood for a barrier, a piece of soft material, such as foam or polystyrene as another reflecting surface
1. Set up the apparatus as shown in the diagram.
2. Set the mobile phone to make a quiet sound that you can hear. Place the mobile phone as close as possible to, or inside, one of the tubes. Put the other end of this tube close to the reflecting surface.
3. Mark the position of this tube on the paper.
4. Set the other tube so one open end is close to the reflecting surface and also close to the other tube.
5. Put your ear to the end of this tube. Turn this tube until the sound from the mobile phone sounds loudest.
6. Mark the position of this tube on the paper.
7. Repeat the investigation with the first tube (containing the mobile phone) in a different position.
8. If you have time, change the reflecting surface.
If you did not have time to change the reflecting surface, suggest:
- one surface that would be bad for reflecting sound.
Work in groups of two or three.
You will need:
- 2 plastic or cardboard tubes and a mobile phone, a large sheet of paper, or 2 A4 sheets taped together, a block or piece of hard plastic, metal or a tile for a reflecting surface, piece of wood for a barrier, a piece of soft material, such as foam or polystyrene as another reflecting surface
1. Set up the apparatus as shown in the diagram.
2. Set the mobile phone to make a quiet sound that you can hear. Place the mobile phone as close as possible to, or inside, one of the tubes. Put the other end of this tube close to the reflecting surface.
3. Mark the position of this tube on the paper.
4. Set the other tube so one open end is close to the reflecting surface and also close to the other tube.
5. Put your ear to the end of this tube. Turn this tube until the sound from the mobile phone sounds loudest.
6. Mark the position of this tube on the paper.
7. Repeat the investigation with the first tube (containing the mobile phone) in a different position.
8. If you have time, change the reflecting surface.
If you did not have time to change the reflecting surface, suggest:
- one surface that would be bad for reflecting sound.
