Mechanics - Energy, Work and Power Flashcards
Define Work
Work is the energy given to a body by a force moving it through a displacement in the same direction as the applied force.
Define Energy
Energy is the ability to do work.
What is the law of conservation of energy?
Energy cannot be created or destroyed, but is converted from one form to another.
What are the two main forms of energy studied @ Leaving cert?
Potential and kinetic.
What is potential energy?
Potential energy is energy due to position or conformation.
What is the formula for potential energy?
E = mgh
What is kinetic energy?
Kinetic energy is energy due to movement.
What is the equation for kinetic energy?
E = 1/2mv^2
What is the equation for mass-energy equivalence?
E = mc^2
What is power?
Power is the rate at which work is done.
Give the equation for power.
P = w/t // e/t
Define efficiency.
Efficiency is output divided by input.
