Energy and Fields Flashcards
(13 cards)
work done
product of force and displacement of body in the direction of the force
kinetic energy
energy possessed by a body due to its motion
force field
region of space in which a body experiences a force without physical contact with another body. it is produced by the presence of another body (or bodies).
gravitational field strength
gravitational field strength at a point is the gravitational force per unit mass on a mass placed at that point
electric field strength
electric field strength at a point is the electric force per unit positive charge placed at that point
what is work done by external force = to
change in potential energy
work done by gravitational or electric force is = to
negative of change in gravitational or electric potential energy
gravitational potential energy def (hint energy store)
energy store for a mass due to its position in a gravitiational field
electric potential energy def (hint energy store)
energy store for charged body due to its position in an electric field
elastic potential energy def (hint energy store)
energy store in an elastic body due to its elastic deformation
principle of conservation of energy
In the absence of any external force, total mechanical energy of system is conserved, where total mechanical energy is the sum of kinetic and potential energy of the system.
why is gravitational force and spring force (or electric force) not considered when calculating work done by external force (on the system)
since gpe, epe (elastic and electric) are already internally included in the total mechanical energy of the system, the mentioned forces that results in these 3 potential energies are internal forces and are no longer considered in work done by external forces.
def power
rate of energy transfer
