Circular Motion and Simple Harmonic Motion

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When Pigs Fly cont.

PhotoElectric Effect

When Pigs Fly

Tan(theta)=V^2/vg

V=(tan(theta)rg)^1/2

V=tan(29.86)(.74)(9.81)

Theoretical velocity=.464989

Experimental velocity=.488162

Percent error=.499% higher than theoretical value. Placement error, string tension, initial force could account for this.

Einstein's Quantum Light Theory

E=hf

Light is a particle (Photon) as well as a wave

15SPF = 1.26V

30 SPF= 1.19V

50 SPF= .97V

50SPF was .22V more effective at blocking out light

Blue=.93V (Highest frequency, therefore most energy)

Green=.68V (Second most frequency) green is important because plants are green and photosynthesize

Red=.53V (Lowest frequency, and lowest energy on the color spectrum)

UV light = constant frequency

to lower the energy you have to add the SPF to reduce the impact of energy

length of string=1.35m

radius of circle= .74m

time for 10 revolutions=22.45s

mass of pig=.156kg

Sin(angle)=.74/1.35

Sin-1(.74/1.35)=29.86 degrees

T=22.45/10=2.245 seconds

C=2(pi)(r)=2(pi)(.74)=4.65 m

Ac=v2/r=(2.07 m/s)2/.74=5.79 m/s2

V=2(pi)(r)/T=4.65m/2.245s=2.07m/s

Fc=mac=(1.35m)(5.79m/s2)=7.82m2/s2

Circular Motion and Simple Harmonic Motion

Cups and Railroad Wheels

The pig accelerates towards the center of circle.

Time and Gravity are inversely proportional.

V= ((Fc)(.74)/(.156))1/2

-the greater the radius, the greater the velocity

- both sides need to be same speed- so when turning wheels shift to keep even

-railroad wheels are shaped like this

worst

outer side r=4.25cm

inner side r=3.75cm

T=1s

v=2rpi/T

.27 m/s outer

.24m/s inner

hf = E

mc^2 = E

best

outer side r=2.5cm

inner side r=3cm

T=1.2s

v=2rpi/T

.13m/s outer

.16m/s inner

the .o3 difference generates SHM motion on trains so only gradual turns are possible

middle

r=.75 cm

constant r

smallest tangental velocity= more control

T=.2s

v=2rpi/T

.24m/s

Radiometer

relates circular motion and simple harmonic motion- need oscillations for energy

amplitude=30cm similar to radius of wheel=30.5cm

A.) This Radiometer allows light to fly off the white side causing the vanes to spin

B.) The radiometer is used to measure radiant energies such as infrared radiation.

C.) The Radiometer can be used as a model of how the seasons have different temperatures based on the distance of the earth from the sun due to it's axial tilt

Distance:

50cm: faster than the human eye

100cm: 4.95s/3revs

150cm: 18.18s/3rev

200 cm: no effect

Simple Pendulum

Energy