Videos By Alpha

Alphabetical Listing: C-D

1. C
   1. Cartesian Diver
   2. Cathode Ray Tube
   3. CD Diffraction
   4. Chladni Plates
   5. Concave Mirror; Blackboard Optics
   6. Concave Mirror, large
   7. Conduction in Liquids
   8. Contraconcave Mirrors (Mirage)
   9. Convection Currents
   10. Convex Mirror; Blackboard Optics
   11. Converging Lens; Blackboard Optics
   12. Crush Soda Can

   13. Curve Ball

2. D
   1. Diffraction Grating
   2. Disappearing Beaker
   3. Diverging Lens; Blackboard Optics
   4. Double Ball Bounce
   5. Double Cone and Plane Trick
   6. Doppler Tuning Fork; slung
   7. Doppler Tuning Fork; rotating
   8. Doppler Reed
   9. Doppler Shift, sidewalk observer
   10. Doppler Shift, car 1 observer
   11. Doppler Shift, car 2 observer

   12. Drinking Duck

Physics Demo Videos

Alpha C	Discussion	Streaming	Download	Demo Page
Cartesian Diver	The diver-shaped glass in the cylinder has a small hole in the bottom. When pressure is applied to the rubber membrane covering the cylinder, more water is forced into the diver, causing an change in its average density. When this density is less than water, the diver will float; when it is more the diver sinks. Done carefully, an equilibrium point can be found where the diver is suspended in the water.	Real	Real MPG	Fluid Mechanics 2B40.30
Cathode Ray Tube	A stream of electrons will be bent by a magnetic field.	Real	Real MPG	E and M 5H30.10
CD Diffraction	The lines on a CD are close enough together to act as a diffraction grating and separate light into its constituent colors.	Real	Real MPG
Chladni Plates	When a two dimensional object is vibrated, patterns of waves can be seen. The sand on the plate collects in the nodes, or areas of no motion, of the waves.	Real	Real MPG	Waves 3D40.30
Concave Mirror; Blackboard Optics	On a concave mirror, the light is reflected back through a focal point.	Real	Real MPG	Optics 6A20.10
Concave Mirror, large	Curved mirrors obviously distort the image. For a concave mirror, the image will appear right-side-up.	Real	Real MPG	Optics 6A20.45
Conduction in Liquids	A bulb has two probes that make an open circuit when initially plugged into the socket. Placing the bulb into ordinary tap water does not complete the circuit. However, add a dash of salt, and the ions are free to carry current, closing the circuit and making the light glow. The more salt, the brighter the bulb.	Real	Real MPG	E and M 5D30.10
Contraconcave Mirrors (Mirage)	Two concave mirrors facing one another can be used to create a hologram. Perhaps this is how some people produce ghostly images?	Real	Real MPG	Optics 6A20.35
Convection Currents	A drop of food coloring is placed water at the top of a glass loop. When one corner is heated, a convection current is started and the food coloring will move around the ring.	Real	Real MPG	Thermo 4B20.10
Convex Mirror; Blackboard Optics	On a convex mirror, the light is reflected back through a perceived focal point situated behind the mirror.	Real	Real MPG	Optics 6A20.10
Converging Lens; Blackboard Optics	A converging (convex) lens focuses light through a focal point before creating a magnified image.	Real	Real MPG	Optics 6A60.10
Crush Soda Can	A small amount of water is heated in a soda can until steaming. The can is then quickly put in cool water, mouth side down. The sudden change in temp causes a sudden change in pressure, making atmospheric pressure higher than the can pressure. Thus, the can collapses under the pressure.	Real	Real MPG	Fluid Mechanics 2B30.15
Curve Ball	A moving, spinning ball will curve due to the addition or subtraction of pressure effects. The side that is spinning in the direction of the motion will have a higher pressure than the side spinning away, thus the ball will curve to the low pressure side.	Real	Real MPG	Fluid Mechanics 2C20.60
Alpha D	Discussion	Streaming	Download	Demo Page
Diffraction Grating	Due to the small slits in a diffraction grating, light can be broken down into its constituent colors. For this source, there seems to be three distinct lines; a red/orange, a faint green and a faint blue.	Real	Real MPG	Optics 6D20.20
Disappearing Beaker	Pyrex and Wesson oil have the same index of refraction. Thus, a small test tube filled with oil set into a larger container of oil will "disappear".	Real	Real MPG	Optics 6A40.30
Diverging Lens; Blackboard Optics	A diverging (concave) lens defuses light.	Real	Real MPG	Optics 6A60.10
Double Ball Bounce	A tennis ball is held in contact with a basket ball, then the two are dropped as one. The basketball has a higher momentum since is has a higher mass. When they hit, the momentum"switches"; i.e. the tennis ball has a momentum equal to that had by the basketball before the collision. The effect is a very fast moving, high bouncing tennis ball.	Real	Real MPG	Mechanics 1N30.60
Double Cone and Plane Trick	Look carefully; the center of mass of the cone is actually rolling down hill. An optical illusion makes it look like its rolling up.	Real	Real MPG	Mechanics 1J11.50
Doppler Tuning Fork; slung	A tuning fork, when slung, will illustrate the doppler shift in frequency. The frequency goes up when the sound is moving towards you while the frequency goes down while it is moving away. .	Real	Real MPG	Waves 3B40.18
Doppler Tuning Fork; rotating	A tuning fork, when rotated, will give a "vibrating" sound illustrating the doppler shift in frequency. The frequency goes up when the sound is moving towards you while the frequency goes down while it is moving away. .	Real	Real MPG	Waves 3B40.18
Doppler Reed	A whistling reed, when rotated, will give a "vibrating" sound illustrating the doppler shift in frequency. The frequency goes up when the sound is moving towards you while the frequency goes down while it is moving away. .	Real	Real MPG	Waves 3B40.25
Doppler Shift, sidewalk observer	The Doppler shift as heard from a passing source: The frequency of the car's horn goes up when the sound is moving towards you and goes down while it is moving away.	Real	Real MPG	Waves 3B40.xx
Doppler Shift, car 1 observer	The Doppler shift as heard from inside the source: The frequency of the car's horn does not change when you are traveling at the same speed as the source.	Real	Real MPG	Waves 3B40.xx
Doppler Shift, car 2 observer	The Doppler shift from a car traveling in the opposite direction as the source: The frequency of the approaching car's horn goes up when the sound is moving towards you and goes down while it is moving away. Notice that the frequency change is higher in car 2 as compared to the sidewalk.	Real	Real MPG	Waves 3B40.xx
Drinking Duck	As the liquid evaporates from the head of the duck, the liquid in the duck heats up (towards room temp) making it rise up the duck's body. When it passes the CM point of the duck, it tips it over, getting the beak wet again. The cool water cools the liquid and the duck stands back up.	Real	Real MPG	Thermo 4C31.30