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Insta - freeze

Dissolved gases in a liquid lower the freezing point temperature. When the gases leave, the liquids is able to freeze.

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Ex 3)

Where is PE max?, KE Max?, PE = 0?,
KE =0? KE = PE?

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Show Me The Physics If PE at A = 10 J, KE = 0

 PE KE A 10 J 0 J B 0 J 10 J D 10 J 0 J

If PE at C = 3 J, KE = ? KE = 7 J

Ex) If the Wf as the pendulum moves from A to B is 1.5 J, what are the KE and PE of the pendulum at the bottom of the swing? PE = 0 J

KE = 8.5 J Wind turbines convert one form of energy into another. What is that conversion? Teachers - Check out this great clipart archive - Wpclipart Kinetic energy to electric energy.

All Pendulums

 PE Max. at     Extremes     KE Max. at     Bottom     PE at Extremes  =     KE at Bottom         KE @ Extreme =   Zero   PE @ Bottom always =   Zero

 Ex 4) 1.0 kg pendulum swings to a height of .20 m above its lowest point.  K.E. of pendulum at lowest point? Ex 4) 1.0 kg pendulum swings to height of .20 m above lowest point.  KE of pendulum at lowest point?

 PE @ A = KE @ B

PE = mgh

= (1.0 kg)(9.8 m/s2)(.20 m)

PE = 1.96 J

PE = KE @ B = 2.0 J Ex) A pendulum is pulled to the side and released. Which plot of d vs PE is correct?  Ex 5) 5.00-kg cart at foot of a hill 10.0 m high. For cart to reach the top of the hill, what is minimum KE of cart in the position shown? [neglect friction.] Ex 5) 5.00-kg cart at foot of hill 10.0 m high. For cart to reach the top of the hill, what is minimum K.E. of the cart in the position shown? [neglect friction.] m = 5.00 kg

h = 10.0 m

KE = ?

KE at bottom = PE at 10.0 m

KE = PE = mgh

= 5.00 kg(9.8 m/s2)10.0 m

KE = 490. J Author H. Christiaen, K.U.Leuven, Belgium

Finding the height of a pendulum
from a pendulum angle      Enrichment

Pendulum Top View

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School blocks YouTube? Use the file below.

Pendulum mounted on a rotating base

School blocks YouTube? Use the files below.