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Student ObjectiveStudent Objective To explain To explain conservation of energyconservation of energy

To identify To identify energy conversionsenergy conversions

When a bowling ball hits the bowling pins, the ball is doing ____________ on the pins.

__________ is transferred from the ball to the pins.

Warm UpWarm Up

Energy

work

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Flashlight InvestigationFlashlight Investigation

What makes a flashlight shine?What makes a flashlight shine? Lets Investigate:Lets Investigate:

1.1. Take batteries out of a flashlight & look at Take batteries out of a flashlight & look at them…them…WhatWhat type of energy do they type of energy do they provide?provide?

2.2. Put batteries back into the flashlight and turn Put batteries back into the flashlight and turn it on…it on…WhatWhat type of energy do you see?type of energy do you see?

3.3. Leave flashlight on for a few minutes then Leave flashlight on for a few minutes then put your hand near the bulb of the flashlight. put your hand near the bulb of the flashlight. What type of energy do your feel?What type of energy do your feel?

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Flashlight ReviewFlashlight ReviewReflections:Reflections:

– How does a flashlight work in terms of How does a flashlight work in terms of energy?energy?

– Where does the energy come from? Where does the energy come from?

What type of energy is this?What type of energy is this?

– Where does the energy go? Where does the energy go?

What type of energy is this?What type of energy is this?

Energy in battery is transferred to the light bulb.

Batteries

to the light bulb

Chemical transformed into electrical

Radiant & thermal

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Flashlight Flashlight ReviewReview Conclusions:Conclusions:

– A flashlight transforms _____________ A flashlight transforms _____________ energy into _______________ energy. energy into _______________ energy. But some ______________ energy was But some ______________ energy was also given off. also given off.

– Do other forms of energy transform? Do other forms of energy transform?

________ ________

Lets find out!Lets find out!

Chemical/electricalradiant (light)

thermal (heat)

YES

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- Energy Transformations and Conservation

Energy Energy TransformationsTransformations Most forms of energy can be Most forms of energy can be

transformed into other forms.transformed into other forms.

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Reading to UnderstandReading to Understand Read pgs 158 – 163. Read pgs 158 – 163. In the graphic organizer answer the In the graphic organizer answer the

questions.questions.

Question Answer

1. What is an energy transformation?

2. What are some examples of transformations between potential and kinetic energy?

3. What is conservation of energy?

Hint: Look at pg. 160-161

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Reading to Understand Reading to Understand QuestionsQuestions Check the answers below with Check the answers below with

yours from your readingyours from your reading

Question Answer

What is an energy transformation?

An energy transformation is a change from one form of energy to another.

What are some examples of transformations between potential and kinetic energy?

Juggling and pendulums show transformations between potential and kinetic energy.

What is conservation of energy?

The law of conservation of energy states that energy cannot be created or destroyed.

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http://physics.weber.edu/amiri/director/dcrfiles/energy/pendulums.dcr