3B Wave Motion

Adding waves model

The black beads of crests are on the crests of the wave form. This is constructi
Catalog: 
3B27.20A
Location: 
Bb4
Bead model. -1(model), -2(equal amplitude, equal frequency template), -3(half amplitude, double frequency template)

Doppler balls

Spin the balls around your head and they make a whistling sound.
Catalog: 
3B40.102
Location: 
Bc1
Yellow and red balls

Doppler Rocket

In the circular mode the rocketis swung over your head.
Catalog: 
3B40.103
Location: 
Bc1
The Doppler shift can be produced with either circular or horizontal motion.

Speaker and Baffle

A small speaker is much louder when placed behind this baffle.
Catalog: 
3B55.30
Location: 
Bc2
Music is played through a small, cheap speaker. The speaker is first held in the hand and then placed behind a small hole in a baffle, with dramatic improvement in sound quality.

Moire patterns

demonstration image
Catalog: 
3B50.40C
Location: 
3_1
Video Encyclopedia :Two transparencies of equally spaced circles on the overhead.

Bell in a Vacuum

Catalog: 
3B30.30A
Location: 
Bc1
An electric bell is placed in an evacuated jar.

Quincke's Tube

The path of the sound can be lengthened on one side by pulling the slide like a
Catalog: 
3B55.40
Location: 
The sound from a small speaker branches in two directions then out the horn. The length of one of the paths can be changed by pulling the slide like a trombone. The sound will constructively and destructively add as the slide is pulled.