Exam 4 Flashcards
What’s the formula for work?
force x distance
What’s the formula for power?
work/time
What’s mechanical energy?
when work is done on an object, object acquires ability to do work
What are the 2 types of mechanical energy?
potential and kinetic
What is potential energy and what does it depend on?
energy of position or configuration; reference point
What’s kinetic energy?
energy of motion
What’s total work?
work done by all forces acting on mass; change in kinetic energy
Where did the concept of conservation of energy came from?
Galileo’s inclines
What’s the condition for conservation of mechanical energy?
no work can be done on the object by a nonconservative force
What’s a nonconservative force? What’s an example?
a force that converts mechanical energy into another form; friction
What’s the formula for efficiency?
work done/energy used
What’s considered the graveyard of useful energy?
heat
What’s the formula for energy efficiency ratio(EER)?
output capacity/input energy
Can kinetic energy be canceled? Why?
no; it’s a scalar
Can momentum be cancelled?
yes, when the object’s mass doubles and its traveling half the speed