Wave Notes

TEKS 5A & 5B
Waves

What is a WAVE?

A wave is a disturbance that travels through space transferring energy

Crest

The top of the wave
Crest is at the top of the toothpaste market!

Trough
The bottom of the wave pigs eat from a trough which resembles the bottom of a wave

Wavelength
The distance between a point on a wave and the same point on the very next wave

Types of Waves
Transverse Waves—waves that move in a perpendicular direction to the particles in the medium in which it’s passing.

Demonstrate a transverse wave with the coil

Compressional (Longitudinal) Waves—waves that move in a direction parallel to the particles in the medium in which it’s passing. Sound waves are compressional waves.
Demonstrate a compressional wave with the slinky.

Refraction
This phenomena is why the plants in the picture seem to have broken stems and the animal’s head appears to be disconnected from its body.

Reflection
The bouncing back of a wave as it hits a surface. The girl in the picture is a reflection off of the aquarium glass.

Resonance
Prolonged vibrations of a material at its natural frequency.
The Tacoma Narrows bridge was destroyed by resonance.

Interference
Wave interference occurs when two waves meet while traveling through the same medium. The amplitudes (heights) of the waves are added at the point that they pass each other.

Constructive Interference
When the two waves displace the medium in the same direction.
http://www.glenbrook.k12.il.us/GBSSCI/PHYS/Class/waves/u10l3c.html

Destructive Interference
When two waves displace the medium in opposite directions
http://www.glenbrook.k12.il.us/GBSSCI/PHYS/Class/waves/u10l3c.html

Polarization
A polarizing lens allows only light waves of a single orientation to pass through.

February 9, 2009

1. Bellringer
2Cs + 2H2 ---> Cs2 + 4H
Calculate the number of moles and grams of each product if you were given 12.4 grams of H2.

2. Waves

Quiz on stoichiometry Friday.

Secret Word of the Week
P1 Crest
P3 Limiting Reagent
P4 Solution
P6 Solvent
P7 Solute

February 6, 2009

WAIVER DAY - NO SCHOOL FOR STUDENTS

February 5, 2009

1. Bellringer

Term- Solution
What does it mean to you? How do you define it and in what context? Provide an example. What problem in science warrants a solution? Explain
(1-2 pages)

2. Teacher guided peer tutoring.

3. Homework - Complete bellringer essay.

February 4, 2009

1. Bellringer
Stoichiometry Problems

1a) How many moles of chlorine gas (Cl2) would react with 5 moles of sodium (Na) according to the following chemical equation? (Balance equation.)
Na + Cl2 --> NaCl
1b) Using the equation (after it is balanced) above, determine the amount of product that can be produced from 24.7 g Na.
1c) How many molecules of product would be produced from 24.7g Na?
__________________________________________________________________________________
2a) In the reaction 2C8H18 + 25O2 --> 16CO2 + 18 H2O, the ratio of volumes of O2 to CO2 is _________________.
2b) If 27.3g of C8H18 are combusted, what mass of water will be produced?
2c) How many molecules of CO2 will be produced?
2d) How many atoms of H are in 2 mol of C8H18?
2e) What is the percentage, by mass, of the H in 2 mol of C8H18?

2. Intro To Waves
3. Homework - find a science website and e-mail it to myscienceclass@yahoo.com

February 2, 2009

Secret Words of the Week
P1 Mutualism
P3 Commensalism
P4 Parasitism
P6 Predation
P7 Symbiosis

February 2, 2009

1. Quiz - Symbiotic Relationships
2. More molar calculations