4-PS3-2 ENERGY

Transcription

4-PS3-2 ENERGY
OKLAHOMA ACADEMIC STANDARD FOR SCIENCE:
4-PS3-2 ENERGY
4TH GRADE
OBJECTIVE:
Students who demonstrate understanding can make observations to provide evidence that energy can be transferred
from place to place by moving objects, sound, light, heat and electric currents.
CORE IDEAS: CONSERVATION OF ENERGY AND ENERGY TRANSFER
1. Energy is present whenever there are moving objects, sound, light or heat.
2. When objects collide, energy can be transferred from one object to another, thereby changing their motion.
3. In such collisions, some energy is typically also transferred to the surrounding air; as a result, the air gets
heated and sound is produced.
4. Light also transfers energy from place to place.*
5. Energy can also be transferred from place to place by electric currents, which can then be used locally to produce
motion, sound, heat, or light.*
6. The currents may have been produced to begin with by transforming the energy of motion into electrical
energy.*
* These core ideas are not included in this lesson plan.
DEFINITIONS OF ENERGY: Energy can be moved from place to place by moving objects or through sound, light,
or electric currents.
Conservation of Energy: Energy is not created or destroyed, only changed in form.
Potential Energy (PE): Stored energy.
Kinetic Energy (KE): Energy of motion. The “death” of Kinetic Energy (no gain in PE) is heat.
That is, Kinetic Energy transfers to a non-restoring form of energy, heat.
Friction: Friction is a force that acts in an opposite direction to movement. It occurs
anytime you rub two objects together. When two things rub against each other, they
both slow down. Because energy = mass x velocity, if the objects lose velocity without
gaining mass, then they have to release some energy to keep the equation equal. One
way for them to release that energy is as heat – loose electrons shooting off into the air.
ASSESSMENT BOUNDARY:
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Assessment does not include quantitative measurements of energy.
4-PS3-2: Energy
MATERIALS REQUIRED:
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Gravitate Kit
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2 rubber hoses
Braces
Legs
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Measuring Tape
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Balls of varying sizes and weights
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Scale (for weighing balls)
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Stopwatch
PREPARATION:
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Set up the track.
Measure and record the length L. _____m
Measure and record the height H. _____m
Measure and record the curve C. _____m
Measure and record the mass of the ball or moving object. _____kg
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4-PS3-2: Energy
PROCEDURE:
Core Idea #1: Energy is present whenever there are moving objects, sound, light or heat.
1. Place the ball at the top of the track and release it. If the top of the track is flat, you may need to give the ball a
gentle push.
2. Measure and record the distance the ball travels each time it is released.
3. Repeat steps 1 and 2 several times to allow the students to observe the transfer of energy.
a. Ask the students to list the types of energy they observe.
(PE sitting at the top of the track; KE as it rolls on the track.)
b. Does the ball always travel the same distance?
c. What causes the ball to roll backwards towards the end of the track?
Assess: Ask questions to help the students identify types of energy exhibited and how energy is conserved.
Core Idea #2: When objects collide, energy can be transferred from one object to another, thereby changing
their motion.
1. Release 1 ball from each end of the track.
a. What evidence of transfer of energy is observed when the two balls collide? (Change in motion)
2. Place 1 ball at the bottom of the track; then release the second ball from the top of the track.
a. What evidence of transfer of energy is observed when the two balls collide? (Change in motion)
b. What differences do you observe in energy transfer when one object is stationary and the other is
moving?
Assess: Ask questions to help the students understand that when 2 objects collide they push on each other and
can change motion.
Core Idea #3: In such collisions, some energy is typically also transferred to the surrounding air; as a result,
the air gets heated and sound is produced.
1. Release 1 ball from each end of the track.
a. Besides the change in motion, what evidence of transfer of energy is observed when the two balls
collide? (Sound)
b. What causes the heat that produces sound? (Friction)
Assess: Ask questions to help the students understand that sound is evidence of the transfer of Kinetic Energy to
heat, through the force known as friction.
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