Colegio San Patricio Physics WORK AND ENERGY Mrs. Nora Guerra Mrs. Martha Fuentes
- Work is done whenever a force (F) is exerted and whenever there is a displacement (s).
- The amount of work done is proportional to both, the force and displacement.
- Work is measured in newton-meters or Joules.
Formula for work W F d W= work F= force d= distance
- In a raindrop: .0001 Joules
- Needed to press a key: .01 Joules
- It´s the energy of motion.
- An object with motion- whether it´s vertical or horizontal- has kinetic energy.
Kinetic energy formula
- Kinetic energy equals the massof the moving object times the square of that object´s velocity, multiplied times the constant ½.
- It´s the energy that can result in the exertion of a force over a distance. It is stored energy.
- Most common= Gravitational PE
Potential energy formula
- Potential energy (joules) =
- mass (kg)*g(m/s 2)* height (m).