Energy Equations Flashcards
Write out the word equation for kinetic energy
Kinetic energy = 1/2 x mass x (velocity)^2
Write out the symbol equation for kinetic energy
Ek (subscript k) =1/2mv^2
Units:
for kinetic energy
mass
velocity
Kinetic energy in Joules - J
Mass - kg
velocity - m/s
Note: Write out the equation for kinetic energy
Always write it in words
Kinetic energy = 1/2 x mass x (velocity)^2
Write out the word equation for gravitational potential energy
Gravitational potential energy = mass x gravitational field strength x height
Write out the symbol equation for gravitational potential energy
Ep = mgh (subscript p)
What is the second way to write the equation for Gravitational potential energy
Write the units
Ep (subscript p) = W x h
Unit for weight = Newtons = N
Weight is a force
remember - m x g = W
height in metres, m
if the question asks for the equation in terms of weight write the above
Units for:
gravitational potential energy
mass
gravitational field strength
height
Gravitational potential energy in Joules - J
Mass - kg
gravitational field strength = assume10N/kg
height = metres, m
Write out the word equation for the elastic potential energy (in an elastic band)
Elastic potential energy = 1/2 x Force x extension
Write out the symbol equation for the elastic potential energy (in an elastic band)
Ee (subscript e) =1/2Fe
Units for
elastic potential energy
Force
extension
Elastic potential energy in Joules - J
Force - Newtons - N
extension - m
Write out the word equation for elastic potential energy (in a spring)
Elastic potential energy = 1/2 x spring constant x (extension)^2
Write out the symbol equation for elastic potential energy
Ee (subscript e) = 1/2ke^2 (only the extension ‘e’ that’s squared.
Units for
elastic potential energy
Spring constant
Extension
Elastic potential energy in Joules - J
Spring constant = Newtons per metre = N/m
Extension - metres - m
