|
Preparation:
Material:
hand drums, CD player, grains of
rice / pins, a bowl filled with water, a stone, milk, food colour, wine glasses,
cardboard tubes, thin plastic foil, cardboard paper, thin slips of paper,
pencil, rubber, Sellotape
Video download
|
Steps:
Situation / Problem:
The children throw a stone into a bowl filled with
water / milk / food colour. Waves appear. Tones produce waves in the air. Can
we also see the tone that we hear?
Exploring Developing Phase:
Experiment 1: Put a CD player next to a hand drum, put rice
grains or pins on the drum, turn on the CD player, turn the volume up and
down.
Experiment 2: Put several glasses filled with different
quantities of water into the middle, the children slide a damp finger over
the edge of the glass, singing sounds are produced
Make a sound cannon:
- glue a circle made of cardboard which has a
little hole in the middle on the opening of a
tube
- draw a thin plastic foil over the other opening
- fold a thin paper slip at a right angle and glue
it on a table
- hold the tube so that the hole points in the
direction of the paper slip
- knock on the plastic foil
|
|
Scientific Explanation:
Experiment 1: Sound travels through the air, reaches the drum
and makes the surface of the drum swing.
Experiment 2: The tones are produced by the finger that rubs
over tiny uneven spots in the glass, that is what makes the glass swing and
produces a sound.
Make a sound cannon: The knocking produces the sound waves that travel
through the tube. Sound waves are air vibrations which push against the paper
slip.
|
