Energy Flashcards
What is energy?
a system’s ability to do work/ make something happen
Kinetic Energy
the energy of motion
What is the relationship between kinetic energy and speed?
as speed doubles, kinetic energy quadruples
Kinetic energy equation
K = 1/2mv^2
Potential Energy
energy associated with a given object’s position in space or other intrinsic qualities of the system
Gravitational Potential Energy
energy that depends on the an object’s position relative to the ground
Equation for gravitational potential energy
U = mgh U = potential energy h = height relative to ground/ zero potential level
What is elastic potential energy?
when a spring is moved from equilibrium
Equation for elastic potential energy
U = 1/2kx^2 k = spring constant x= magnitude of displacement from equilibrium
Equation for total mechanical energy
E = U + K
What is the first law of thermodynamics?
Conservation of mechanical energy - energy is never created or destroyed - only transferred
What are conservative forces?
those that are path independent and do not dissipate energy
What are nonconservative forces?
They are path dependent and cause dissipation of mechanical energy of a system.
Examples of nonconservative forces
friction, air resistance, or viscous drag
What is work?
the process by which energy is transferred form one system to another
Equation for work
W = F*d = Fdcostheta theta = angle between the applied force vector and the displacement vector d = magnitude of displacement through which the force is applied
How do you interpret volume pressure curves?
the area under the curse / enclosed by is the work done
What is the work energy theorem?
expressed the relationship through this equation:
Wnet = deltaK = Kf - Ki
What is isovolunmetric/ isochoric process?
When the volume doesn’t change with pressure or vice versa
What is the equation for work with isobaric processes?
W = PdeltaV p = pressure v = volume
What is power?
Power is the rate at which energy is transferred from one system to another
What is the equation for power?
P = W/t = deltaE/t
What is the unit for power?
Watt = J/s
What is mechanical advantage?
the ratio of magnitudes of the force exerted on an object by a simple machine (Fout) to the force actually applied on the simple machine (Fin)
What is the equation for mechanical advantage?
MA = Fout/Fin
What is the equation for efficiency?
Efficiency = Wout/Win = (load)(load distance)/(effort)(effort distance)
