Energy Flashcards
What is energy
The ability to do work, or to produce a change
What is kinetic energy?
The energy of motion, or the energy an object has because it is moving
What is the Work-Kinetic Energy theorem?
The net work done on an object equals its change in kinetic energy
What is potential energy?
The energy stored as a result of position of an object or the configuration of atoms in a substance
What is gravitational potential energy?
Energy that an object has due to its position (height) in a gravitational field
What is elastic potential energy?
Energy stored in springs or other springy things
Define mechanical energy and list at least three examples
Energy involving forces and motion; kinetic, gravitational potential, and elastic potential
What is the Law of Conservation of Mechanical Energy?
The total mechanical energy of a closed system remains constant. The sum of all mechanical energies are constant.
What is a closed system?
When there are no external forces acting on a system and there are no changes in the mass of a system. No energy is transferred into or out of the closed system
Describe energy transfers that occur when a ball is thrown into the air and allowed to freely fall back to its original position
Work is done on the ball to get it moving upward. Work becomes kinetic energy, and the kinetic energy decreases and gravitational PE increases as the ball rises. Gravitational PE decreases and kinetic energy increases as the ball falls down. In all the motion, total energy remains constant
How is mechanical energy lost in a system, such as a rollercoaster or pendulum?
The energy is converted to an unusable, non-mechanical form, usually thermal, due to friction or bending/stretching materials (deformation)
