Term
What formula determines kinetic energy? 

Definition
K = 1/2mv^{2}
K is kinetic energy
m is mass
v is velocity 


Term
Equation for potential energy 

Definition
U = mgh
U is potential energy
m is mass
g is gravity
h is height 


Term

Definition
The process by which energy is transferred from one system to another. 


Term
Equation for power and the units of power 

Definition
P = W/t
P is power in Joules/second (J/s)
W is work in in J
t is time in s



Term
What is mechanical advantage and how is it determined? 

Definition
Mechanical advantage = F_{out}/F_{in}
F's represent the force exerted on an object by a simple machine (F_{out}) and the force applied to the machine (F_{in}) 


Term
How do pulleys decrease the force needed to move an object? 

Definition
The pulley makes it so that two strings are supporting the weight of the object. Now when the string is pulled the object will move half the distance of the length of string pulled but this will only require half of the original force necessary. Every pair of pulleys added equals a twofold decrease in force needed but a twofold increase in length of rope. ie 2 pairs of pulleys = 4 times, 3 pairs of pulleys = 6 times 

