Work,Energy & Power Flashcards
Work
It is the product of force and displacement along the direction of force.
w=F*d
Energy
Ability to do work
Mechanical energy
- kinetic energy
- potential energy
Kinetic energy
Energy of object due to its motion.
Ek=1/2mv^2
Potential energy
Energy stored in object
Gravitational Energy
Energy of an object due to its position in gravitational field.
Eg=mgh
Elastic Potential energy
Energy stored in object due to deformation.
Heat
workdone of resistive forces
Heat= resistive forces* distance travelled
Law of conservation of energy
Energy cannot be created but it can be transferred from one form to another. Total energy of the universe is constant. In any particular system, total input energy= total output energy.
Power(p)
workdone/Energy per unit time.
P=w/t
=F.s/t
=Fv
Efficiency
n=useful output energy/ total input energy *100%