Please be Seated Summer Programs for PreCollege Students

Please be Seated

Summer Programs for Pre-College Students

New from Lecture-Demonstration Now on a two-DVD set: The classic four-hour video collection: Demonstrations in Acoustics for only $20. Discount for direct cash Sales. Inquire in front. Dr. Richard E. Berg, demonstrating over 70 experiments, in 29 titled segments, covering vibrations, waves and sound.

You are welcome to visit our Physics Question of the Week http: //www. physics. umd. edu/lecdem/outreach/QOTW/active/questions. htm

Physics is Phun Electronic Mailing List

Water Physics is Phun May 2009 Image compliments of http: //www. inmagine. com/v 3058059 -photo

Topics: Physical properties Electrical properties Changes of State Atmospheric phenomena

Physical Properties of Water Density = 1 g/cm 3 = 1 kg / liter o Specific Gravity = 1. 000 @ 3. 98 C o o Specific Heat = 1 cal / gram C = 1 Btu / lb F Heat of Fusion = 80 cal / gram = 144 Btu / lb Heat of Vaporization = 540 cal / gram = 970 Btu / lb

Weight and Pressure Equilibrium tubes Crush the can using atmospheric pressure

Quiz question: What animal has the highest blood pressure? Mammal, fish, bird, or reptile?

Quiz question: What animal has the highest blood pressure? Quiz answer: The giraffe!!

Pascal’s Law Pressure is distributed uniformly throughout a confined fluid. Hero’s Fountain (Hero of Alexandria)

Buoyancy and Archimedes’ Law An object immersed in a fluid experiences a buoyant force equal to the weight of the fluid displaced.

Quiz Question

Adhesion and Cohesion: Surface Tension Thread loop on water Capillary tubes

Dilatancy

Electrical Properties 1. Conductivity 2. Polarization - wood - water

Superheated water in a Microwave Oven

Changes of State

Ice Crystals

Freezing and melting Putting salt on snow and ice The Ice Bomb

Evaporation and Condensation Can collapse by condensation Freezing water by pumping

Sublimation Ice disappears in freezer or sub-freezing weather Frost patterns on windows (Ice Ferns)

Hailstones Form in layers Can be seen using polarized light

Water in the Atmosphere

Rainbow Mie scattering

Rainbow

Double. Rainbow

Rainbow with Supernumerary Arc

Glass Bead Rainbow N 1 -43

“World’s largest human rainbow” 31, 000 people at the Polytechnic University of the Philippines.

Correct Rainbow! South side of Route 50 on Kent Island, MD

Glory Diffraction effect

Glory 1

Glory 2

Ice crystals in the atmosphere

Pencil and Plate Ice Crystals

Dispersion by Hexagonal Crystal

Sundog Dispersion effect

Sundog with Sun Pillar

Halo Dispersion effect

Halo

Halo with Sundog and Sun Pillar

“Fire Rainbow” Sunlight enters the hexagonal plate crystals' vertical side faces and leaves through their bottom faces, is refracted (as through a prism) and separated into an array of visible colors

Various atmospheric Phenomena

Wisdom for the Year

If you are not part of the solution, you are part of the precipitate.

The End See you next year! We are on the web at http: //www. physics. umd. edu/lecdem/ Animated Gifs compliments of bellsnwhistles. com