ligase elementary school physics table of contents energy types & conversions magnetism...
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Types of Energy
• Heat - the motion of molecules
• Mechanical - motion of objects
• Sound - vibration
• Chemical - chemical reactions
• Light - visible and invisible waves
• Electrical - electricity & magnetism
Conservation of Energy
• Definition: energy cannot be created nor destroyed, but can be transferred from one form to another.
Energy Transfers• One form of energy can turn into another form.
For example: – A ball thrown against the wall represents
mechanical energy. The ball does not bounce back at the same speed, in part, because some of the mechanical energy is converted to sound and heat
Energy Transfer Activities
• Bring in different toys and household items that illustrate multiple energy transfers. Have students identify each energy in the toy/item.
• Most energy that is “wasted” in an energy transfer is converted to heat.
Energy Transfer Activities
• Batteries (chemical)
• Electricity (electrical)
• Motor turns (mechanical)
• Motor makes noise (sound)
• Motor gets warm (heat)
• Wheels turn (mechanical)
• Friction on the floor (heat)
Energy Transfer Activities
• Have students make “Rube Goldberg” drawings illustrating multiple energy transfers. Each drawing should include a number of tasks leading up to a final goal (ex. making toast).
Gravitational Potential Energy• The stored energy of position.
• Weight (N) = mass (kg) x gravity (9.8 m/sec/sec)– 100 kg x 9.8 m/sec2 = 980 N
• GPE = weight x height– 980 N x 10 m = 9,800
10 m
100 kg
Kinetic Energy
• The energy of motion.
• KE = (m x v2) / 2– (100 x 52) / 2 = 1,250
100 kg
Average Velocity5 m/sec