Physical Science 20 2019 Final Study Guide

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Waves Unit

Resonance-Occurs when one object is vibrating at its natural frequency (harmonic) forces another object to vibrate.

First Harmonic- f=fo

Is Generated at low frequencies

Has 2 nodes or points of no displacement at the 2 ends

Has 1 anti-node or point of max displacement in the middle

Second Harmonic -f=2fo

Has 3 nodes and 2 anti-nodes

Is generated twice the frequency as the 1st harmonic

The nodes are at both ends and 1 in the centre

Is separated by an anti-node

Third Harmonic

Has nodes and 3 anti-nodes

Is generated at greater frequency

Frequency- Frequency is defined as "

Heat Unit

Lesson 3- Thermal Expansion

Thermal Expansion occurs in

Thermometers

And atoms and molecules

This occurs because of the distance between molecules increases (gets larger) as their thermal energy increases (gets larger)

Where does Thermal Expansion Occur ??

Bimetallic strips in thermostats

Circuit Breakers

Railway Rails to keep them from expanding

When designing bridges, concrete floors, and railways

Liquid Thermometers

The Liquids in thermometers rise as temperatures do; they contract (get small) when the temp cools

Alcohol, mercury, and kerosene are often used because they expand at constant rates.

Metal has a higher Coefficent of expansion than glass; it expands more

Metal expands when heated ; so does the hole

Metal expands away from the jar when it is heated

The Expansion of Water

Most substances expand and contract uniformly when heated or cooled

Water however is different

As it cools, its volume decreases (gets smaller) untill 4 degrees c

Below 4 degrees c, volume starts to expand because of it's

Ice cubes usually are curved upwards after freezing

Linear Expansion Formulas to have down

Linear Expansion formula =Delta L = coefficient of linear expansion times the original length times the temperature change

Volume expansion formula = Delta V =B(coefficient of volume expansion) times the V which is original volume times the change in temp

Heat Equations

K=C +273.15

C=K-273.15

CHEM UNIT

Definitions-