Chapter 15 - Mechanics Flashcards
1st Law of Thermodynamics- Law of Conservation
Energy, under normal conditions, cannot be created or destroyed- simply transformed from one type of energy to another
Second Law of Thermodynamics
Some of starting energy will be lost as heat- any time you do work
Kinetic Energy
Energy of motion- vertical or horizontal motion
Types of Kinetic Energy
vibrational, rotational, tranlational
kinetic energy equation
KE = 1/2 x mv
where KE in Newtons
m = mass of object
v = speed of object
Potential energy
stored energy
Exists whenever an object that has mass has a position within a force field
Potential Energy equation
PE = mgh
Where m = mass
g= gravitational acceleration of the earth (9.8m/s2)
h = height above earth’s surface
Elastic Potential Energy
the energy stored in elastic material as the result of stretching or compressing
Stored in rubber bands, bungee cords, trampolines, springs, etc…
Hooke’s Law
If a spring is not stretched or compressed, there is no elastic potential energy stored in it
Zero Potential Energy Position
equilibrium position that the spring naturally assumes when there is no force applied to it
Force required to stretch a spring
PE = kx (squared) / 2
K = spring constant
x= amount of compression
Force
Push or Pull upon an object resulting from the object’s interaction with another object
Frictional Force
force that resists the relative motion of objects that are in contact with each other
Tension Force
the force required to pull an object (opposite of compression)
Normal Force
the force on an object caused by the normal interaction between two objects
