Reporting Category #2Forces, Motion, and

Energy

Energy Forms

• Many forms of energy exist around us.

• Energy cannot be created or destroyed, only changed from one form to another.

Some Energy Forms

• Mechanical• Heat• Nuclear• Electrical

• Light• Sound• Chemical• Electromagnetic

Turning on a lamp

Bulb Filament Electrical to light

gets hotter,

glowing

Burning coal Fossil fuel Chemical to heat

gets hotter, glowing,

evaporating

Earthquake Buildings Heat to sound cracking, crumbling

Phosphorescence

Fire fly Chemical to light

glowing

Playing a violin String Mechanical to sound

vibrating

Potential Energy

• Potential energy is energy that is stored in an object.

• If you stretch a rubber band, you will give it potential energy. As the rubber band is released, potential energy is changed to motion.

Kinetic Energy

• Kinetic energy is energy of motion.• A rubber band flying through the air

has kinetic energy. When you are walking or running your body is exhibiting kinetic energy.

• Potential energy is converted into kinetic energy.

Potential & Kinetic Energy

• The apple hanging from the branch has __________ energy. Potential energy is __________ energy. Potential energy changes to ___________ energy when the apple starts to fall. Would an apple sitting on the ground have potential energy? Kinetic energy is _________. Anything in motion has energy. Would an apple sitting still on the ground have kinetic energy?

Potential & Kinetic Energy

• The diver standing on the diving board has ________ energy. Potential energy becomes _________ energy when he dives off the board. Potential energy is _________ energy. _________ energy is the energy of motion. The diver's potential energy __________ as he climbs up the ladder.

Potential & Kinetic Energy

• The ax has the most __________ energy at its highest point, just before it starts to fall. As the ax starts to fall, potential energy changes to ____________ energy. The ___________ energy of the ax is greatest just before it strikes the wood when it is moving at its ___________. The instant the ax strikes the wood, kinetic energy is transferred ________________________. The ax stops moving, but wood chips fly everywhere.

Newton’s Laws of Motion

• Newton’s Law of Inertia• An object at rest tends to

stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force

Newton’s Laws of Motion

• Newton’s Law of Force and Acceleration:

• As the force acting upon an object is increased, the acceleration of the object is increased. As the mass of an object is increased, the acceleration of the object is decreased.

Newton’s Laws of Motion

• Newton’s Law of action-reaction

• For every action there is an equal and opposite reaction.

• If you lean against the wall, you don't just fall through it. The wall pushes back on you as hard as you push on it, and you and the wall stay in place.

Electromagnetic Wave

• Electromagnetic wave: Transverse waves that are produced by the motion of electrically charged particles. Ex: The Light Spectrum