click below
click below
Normal Size Small Size show me how
Physical Science
Chapter 8 Test
| Question | Answer |
|---|---|
| Block and Tackle | Multiple pulley system. Mechanical advantage for pulleys in a block and tackle = numbers of pulleys used |
| Compound Machine | a device that combines two or more simple machines |
| First Class Lever | Lever in which the fulcrum is in the middle |
| Fixed Pulley | a pulley attached to something that does not move. |
| Fulcrum | The fixed point around which a lever pivots |
| Ideal Machine | machine in which work input equals work output; no friction; 100% efficiency |
| Input Force | a unit of work equal to one newton-meter |
| Kinetic Energy | the energy an object has due to its motion |
| Lever | a rigid bar that is free to move around a fixed point |
| Machine | Machine a device that makes work easier |
| Mechanical Advantage | the number of times the force exerted on a machine is multiplied by the machine |
| Mechanical Efficiency | a quantity, usually expressed as a percentage, that measures the ratio of work output to work input in a machine |
| Movable Pulley | a pulley in which one end of the rope is fixed and the wheel is free to move |
| Output Force | the force that is exerted by a machine |
| Power | the rate at which work is done |
| Pulley | a simple machine that consists of a rope that fits into a groove in a wheel |
| Radius | The distance from the center of a circle to a point on the circle |
| Screw | a simple machine that consists of an inclined plane wrapped around a cylinder |
| Second Class Lever | input force is between the fulcrum and the load |
| Watt | unit for power |
| Wedge | a V-shaped object whose sides are two inclined planes sloped toward each other |
| Wheel and Axle | a simple machine that has a center rod attached to a wheel |
| Work | force exerted on an object that causes it to move |
| Work Input | the work done "ON" a machine |
| Work Output | work done "BY" the machine |