# 7th GRADE SCIENCE : Article 27 : Kinetic energy and energy conservation.

* Activity 2.21   :   Roller coaster and energy.                             ( 11/27/17   Monday )

ENERGY CONSERVATION.

2.21.a        Roller coaster and kinetic , potential energies.

Watch these pics and draw the roller coaster in your paper
indicating in each point what kind of energy is acting and how
potential and kinetic energies are changing in one another.

PICTURE 1                                     PICTURE 2                                 PICTURE 3

You can remember here what kinetic energy is.

( 10 points ).

2.21.b        Roller coaster. Work out potential and kinetic energies.

Check the following roller coaster and considering each points hight
and the speed given, work out potentials and kinetics energies at the
different spots at this roller coaster.

( 10 points ).

* Activity 2.22: Total mechanical energy, kinetic plus potential energies.  ( 11/28/17  Tuesday )

2.22.a      Check the paper given  to you and work out the total Mechanical energy the ball
has at every different spot on the hills.

( 10 points ).

2.22.b     At the following LINK check what Mechanical energy is and what it has to do
with potential and kinetic energy.
Open a google doc file and explain there what mechanical energy is and explain
also what relationship is established among mechanical and kinetic and potential
energies.

( 10 points ).

* Activity 2.23   :   Roller coaster simulator.                                         ( 11/29/17   Wednesday )

2.23.a        Roller coaster. Work out potential and kinetic energies.

- Check this simulator on a roller coaster and explain whats happening at the different most
important spots on it.  Draw the path the car follows and write down the cars biggest and smallest speed and say in which place or spot on its way the car gets them.

( 5 points ).

2.23.b        Come up with a situation, like a roller coaster or you riding a bike on a hill, in
which you indicate your mass, the hight, and then work out kinetic, potential and
mechanical energies.

( 10 points ).

2.23.c     At the following LINK check what Mechanical energy is and what it has to do
with potential and kinetic energy.
Open a google doc file and explain there what mechanical energy is and explain
also what relationship is established among mechanical and kinetic and potential
energies.

( 10 points ).

* Activity 2.24   :   Mechanical energy important statements.            ( 11/30/17   Thursday )

energy

1.  What is the mechanical energy?.

2.  What do kinetic energy and potential energy have to do with mechanical
energy?.

3. What does law of conservation of energy say?.

4. Can mechanical energy be destroyed?.
What can it be converted to?.

5. What the mechanical energy of an object is associated with?.

6. Do heat and mechanical energy have some kind of connection?
Which one?.

7. The job of a hydroelectric plant is to make electrical from the mechanical
energy.  How and from what kind of matter stored in dams?.

8. If an object contains mechanical energy, What ability does it have to?.

9. Every object that has motion has mechanical energy. Is it true?
Why?.

10. Every object that has a high position but does not move, cannot show
mechanical energy. But every object in the same situation but in motion,
does show mechanical energy.  WHY?  Why only objects in motion can show
mechanical energy?.

( 10 points ).

2.24.b     At the following LINK check what Mechanical energy is and what it has to do
with potential and kinetic energy.
Open a google doc file and explain there what mechanical energy is and explain
also what relationship is established among mechanical and kinetic and potential
energies.

( 10 points ).

* Activity 2.25 : Catapult involves kinetic, potential and mechanical energies.    ( 12/1/17   Friday )

2.25.a        Build a catapult like this following your teachers instructions.

1)  How does the catapult work?.

2)  Where does the force and energy come from to make it work?.

3)  What kind of energy is transferred to?.

4)  Draw an outline and explain how you did it.

( 25 points ).