Sunday, November 4, 2012

Real World: Work, Force, Energy and Motion (Video Notes)

Work: the use of force to move an object a certain distance

When 'work' is done, the force must move in the same direction as the object's motion.

Work= Force x distance
 W=Fd
W=Newtons x meters
Newton x meters= Joules
Joules is the unit for work

Work can also be understood as a transfer of energy.

Energy is related to work.

2 types of energy: Potential (stored) energy and kinetic energy

A still object can still have energy within the system, that energy is potenital energy.

When a still object is suddenly put in motion the potential energy becomes kinetic energy, or the energy of motion.

Gravitational force has an affect on potential energy due to the fact that the distance of the object from the ground affects potential energy.

GPE=mgh
GPE= mass x gravity x height (meters)
Mass x gravity= Weight= Newtons

GPE= Weight(Newtons) x Meters
The unit for GPE is Joules.

Kinetic energy depends on mass and velocity.
KE= 1/2 mv^2