domingo, 22 de agosto de 2010

vocabulary Nº1, Nº2, Nº3

VOCABULARY Nº1


FORCE:A push or pull exerted by one object on another.




FRICTION:
A force that opposes the motion of an object in contact whit a surface.




DRAG FORCE:
A force that opposes the motion of an object through a kiquid or gas.







GRAVITY:
A force of attraction that exists between  all objects with mass.







NET FORCE:
The combined effect of all the forces acting on an object.




BALANCED FORCE:
Forces that cancel each other out when acting together on a single object.






UNBALANCED FORCES:
Forces that do not cancel each other out when acting together on a single object.






INERTIA:
The tendency of an object to oppose a change in motion.






MOMENTUM:
The mass of an object multiplied by its velocity.




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VOCABULARY Nº 2:


POTETIAL ENERGY:
The energy stored in an object or material .




GRAVITATIONAL POTENTIAL ENERGY:
The potential energy of an object located above the ground.




KINETIC ENERGY:
The energy of a moving object.




WORK:
Force applied to an object times the distance the object moves.




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VOCABULARY Nº 3


SIMPLE MACHINE:
A device with few parts that makes it easier to do work.







EFFORT FORCE:
The force applied to a machine.




RESISTANCE FORCE:
The force that a machine acts against.




LEVER:
A simple machine made of a rigid bar on a pivot point .





FULCRUM:
The pivot point of a laver.




MECHANICAL ADVANTAGE:
The number of times a machine multiplies the force applied.




PULLEY:
A grooved wheel that turns by the action of a rope in the groove.





WHEEL AND AXLE:
A simple machine made of a handle or axis attached to the center of a wheel.