Work and Energy

Work and Energy

1. Work Done by a Constant Force

   • work is the energy transferred to an objectt when a force moves it through a distance
   • In joules
   • If the force causing an object to undergo a displacement is at an angle to the displacement, only the component of the force in the direction of the displacement does work on the object
   • under certain condition, zero work is done on an object even if the object experiences an applied force or is in motion

2. Kinetic Energy and the Work-Energy Theorem

   • The energy of motion. Scalar quantity measured in joules
   • the work energy theorem states that the total work done on an object equals the change in the objects kinetic energy, provided there is no change in any other form of energy

3. Gravitational Potential Energy at Earth's Surface

   • gravitational potential energy is the energy possessed by an object due to its elevation above Earth's surface. scalar quantity measured in joules.
   • Eg is always stated relative to a reference level.
   • Eg of an object depends on its mass, the gravitational field in which the object is located, and the object's height above a reference level

4. law of energy conservation

   • states that for an isolated system, energy can be converted into different forms, but cant be created or destroyed
   • the work done on a moving object by kinetic friction results in the conversion of kinetic energy into thermal energy
   • can be applied to solve a variety of physics problems

5. elastic potential energy and SHM

   • hookes law states that the magnitude of the force exerted by or applied to a spring is directly proportional to the displacement the spring has moved from equilibrium