Quiz 4a (11.12.2020) Flashcards
A combination of energy and matter make up the universe. Energy is…
mover of substances, both a thing and a process, observed when it is being transferred or being transformed, a conserved quantity
____ is a property of a system that enables it to do work
Energy
If an object has matter, it has ___
energy (on a molecular level)
___ involves force and distance
Work
Work is…
force times distance
What two things occur whenever work is done?
application of force and movement of something by that force
____ as much work is done in lifting 2 loads 1 story high versus lifting 1 load the sam vertical distance
twice
___ as much work is done in lifting a load 2 stories instead of 1 story
twice
What is the unit for work?
newton-meter (Nm) or joule (J)
Power is…
the measure of how fast work is done
Power equals
work done divided by time interval (or energy divided by time)
Unit of power =
joule per second, called the Watt after James Watt, developer of the steam engine
1 kilowatt equals __ watts
1000
Mechanical energy is due to___
position or to motion, or both
What are the two forms of mechanical energy?
Potential and kinetic
