click below
click below
Normal Size Small Size show me how
Science flash card
Term | Definition |
---|---|
work | activity involving mental or physical effort done in order to achieve a purpose or result. |
power | the ability to do something or act in a particular way, especially as a faculty or quality. |
joule | the SI unit of work or energy, equal to the work done by a force of one newton when its point of application moves one meter in the direction of action of the force, equivalent to one 3600th of a watt-hour. |
watt | the SI unit of power, equivalent to one joule per second, corresponding to the power in an electric circuit in which the potential difference is one volt and the current one ampere. |
horse power | a unit of power equal to 550 foot-pounds per second (745.7 watts). |
machine | an apparatus using or applying mechanical power and having several parts, each with a definite function and together performing a particular task. |
mechanical advantage | working or produced by machines or machinery. |
efficiency | the state or quality of being efficient. |
lever | a rigid bar resting on a pivot, used to help move a heavy or firmly fixed load with one end when pressure is applied to the other. |
wheel and axle | a simple lifting machine consisting of a rope that unwinds from a wheel onto a cylindrical drum or shaft joined to the wheel to provide mechanical advantage. |
inclined plane | a plane inclined at an angle to the horizontal. a sloping ramp up which heavy loads can be raised by ropes or chains. |
wedge and screw | A wedge is in general a triangular object which is placed between two objects to either hold them in place or is used to move one relative to the other. For example, the following shows a wedge under a block that is supported by the wall |
pulley | a wheel with a grooved rim around which a cord passes. It acts to change the direction of a force applied to the cord and is chiefly used (typically in combination) to raise heavy weights. |
compound machine | Usually the term refers to the six classical simple machines which were defined by Renaissance scientists: Lever, Wheel and axle, Pulley, Inclined plane, Wedge, and Screw. |