Week 9 - Work, Energy And Power Flashcards
What is mechanical work?
The product or force (N) and displacement (m)
What is the work equation? What are the units?
Work = force x displacement (m)
Joules (j)
What is the equation for power and what are the units?
Power = force (N) x velocity (m.s^-1)
OR !
Power = force x distance / time
Units: Watts
What is mechanical energy?
The capacity to do work.
What are the three types of mechanical energy?
Kinetic
Potential
Thermal
What is kinetic energy ?
Anything that moves
What is potential energy?
Anything that has the potential to move
What is thermal energy ?
Objects containing heat
Equation for KE and what are the units?
KE= 1/2 x mass x velocity^2
=1/2mv^2
Units= joules (j)
Potential energy : gravitational energy equation and the units it is measured in
GPE = mgh
= mass x gravity x height
Units= joules
What is the mechanical energy law of conservation ?
When gravity is the only acting external force , a body’s mechanical energy remains constant.
What is the equation for the law of conservation?
C = KE + PE
What is the principle of work and potential energy?
Work = change in KE + change in PE + change in TE
Where does the body store potential energy. Give an example.
Energy can be stored in the elastic tissues in the body and reused later.
What is elasticity?
The tendency to return to normal shape after distortion.
