CH6: Energy Flashcards
list the 6 types of energy stores
kinetic store, gravitational potential store, chemical potential store, elastic potential store, internal store, nuclear store
formula and SI unit of energy in the kinetic store
Ek = 1/2 mv^2
SI unit: joules (J)
what happens when object is stationary in terms of energy?
energy in the kinetic store will be 0 J.
formula and SI unit of energy in the gravitational potential store
Ep = mgh
SI unit: joules (J)
what happens when an object is placed on the top of a slope in terms of energy?
object will have energy in the gravitational potential store that is the product of its height, mass, and gravitational force.
list the 4 types of pathways in terms of energy
mechanical, electrical, thermal, propagation of waves
state the principle of conservation of energy
the principle of conservation of energy states that energy cannot be destroyed nor created but can only be transferred from one energy stores to another energy store. the total energy in an isolated system is constant.
(total initial energy = total final energy)
define work
the product of force acting on an object and the distance travelled by the object in the direction of the force.
formula and SI unit of work
Wd = force x parallel distance
SI unit: joules (J)
define power
power happens when work is done or energy is transferred during a time period.
formula and SI unit of power
P = Wd/t or E/t
SI unit: watts (W) or joules per second (J/s)
formula of power when it is done at constant velocity
P = force x constant velocity
[P = (force x // distance) / time
= force x (// distance / time)
= force x velocity ]
