11/10/09

Post date: Nov 09, 2009 9:40:32 PM

Bell Ringer: What does it mean to say that energy is conserved?

    • Conservation of Energy Notes

      • Energy cannot be created or destroyed, only transferred between objects and between forms

      • Types of energy:

        • PE (gravity)

        • KE (movement)

        • heat

        • light

        • sound

        • chemical (bonds between atoms)

        • nuclear (forces within the nucleus of an atom)

      • Energy changes between these forms to allow ANYTHING to happen

        • Ball rolls down a ramp: PE to KE (and heat from friction)

        • Person moving: Chemical (from food) to Kinetic

      • To solve problems, set energy at one time equal energy at a later time

        • Identify which types of energy will be present at each moment (may be more than one at a time)

        • Replace energy types with equations for energy

        • Fill in all known variables and solve for the unknown.

    • Page 230: 9-11 due tomorrow