Review notes
- 1. PHYSICS REVIEW Summary of concepts Revision activity: Find someone who… Individual work: review worksheets
- 2. BIG IDEAS Energy cannot be created nor destroyed . Energy is converted from one form to another. An object that has energy can do work . Work is done when energy is transferred from one object to another or changed from one form to another.
- 3. Image source: http://www.greenearthproject.com/Forms2.html
- 4. SUMMARY OF CONCEPTS: If h is doubled , the GPE is doubled . If h is tripled , the GPE is also tripled . If speed (velocity) is doubled (2x), the Kinetic Energy increases ( 4x or 2 2 ). If speed (velocity) is tripled (3X ), the KE increases 9x or 3 2 . The GPE at the top changes to KE at the bottom . GPE = w x h or GPE = mgh
- 5. 1. PE = KE 2. Work = Energy Work = PE gained = KE Work = KE WORK AND ENERGY
- 6. POTENTIAL ENERGY Energy is stored , ready to act e.g. Gravitational PE, Elastic PE GPE = mass x gravity x height weight x height Force x distance = Work GPE = gravitational potential energy (J) m = mass (kg) g = gravity 10 (m/s/s) h = height (m) KINETIC ENERGY Energy due to movement e.g. Heat, Sound, Light, Mechanical Kinetic Energy = 1/2 the product of the mass times the square of the velocity KE = mv 2 /2 KE = kinetic energy (J) m = mass (kg) v = velocity (speed) (m/s) WORK Force exerted on an object making it move through a distance occurs with energy transfer Work = Force x distance W = F x d W = work (J) F = force (N) d = distance (m)