Term
|
Definition
| A wedge is a device that is thick at one end and tapers to a thin edge at the other end. |
|
|
Term
|
Definition
| A ramp is an example of a simple machine called an inclined plane. An inclined plane is a flat, sloped surface. |
|
|
Term
|
Definition
| A screw can be thought of as an inclined plane wrapped around a cylinder. This spiral inclined plane forms the threads of the screw. |
|
|
Term
|
Definition
| A lever is a rigid bar that is free to pivot, or rotate, on a fixed point. The fixed point that a lever pivots around is called the fulcrum. |
|
|
Term
|
Definition
| A pulley is a simple machine made of a grooved wheel with a rope or cable wrapped around it. |
|
|
Term
|
Definition
| A wheel and axle is a simple machine made of two circular or cylindrical objects fastened together that rotate about a common axis. |
|
|
Term
|
Definition
| The ideal mechanical advantage of a compound machine is the product of the individual ideal mechanical advantages of the simple machines that make it up. |
|
|
Term
|
Definition
| Work is done on an object when the object moves in the same direction in which the force is exerted. |
|
|
Term
|
Definition
| force times distance = work |
|
|
Term
|
Definition
| Power equals the amount of work done on an object in a unit of time. |
|
|
Term
|
Definition
| A machine is a device that allows you to do work in a way that is easier or more effective.A machine makes work easier by changing at least one of three factors. A machine may change the amount of force you exert, the distance over which you exert your force, or the direction in which you exert your force. |
|
|
Term
|
Definition
| The force you exert on the machine is called the input force. |
|
|
Term
|
Definition
| The force the machine exerts on an object is called the output force. |
|
|
Term
|
Definition
| The input force times the input distance is called the input work. The output force times the output distance is called the output work. |
|
|
Term
|
Definition
| A machine’s mechanical advantage is the number of times a machine increases a force exerted on it. |
|
|
Term
|
Definition
| The efficiency of a machine compares the output work to the input work. Efficiency is expressed as a percent. The higher the percent, the more efficient the machine is. If you know the input work and output work for a machine, you can calculate a machine’s efficiency |
|
|
Term
|
Definition
| To calculate the efficiency of a machine, divide the output work by the input work and multiply the result by 100 percent. |
|
|
Term
| mechanical advantage of an inclined plane |
|
Definition
| You can determine the ideal mechanical advantage of an inclined plane by dividing the length of the incline by its height. |
|
|
Term
| mechanical advantage of a wedge |
|
Definition
| The ideal mechanical advantage of a wedge is determined by dividing the length of the wedge by its width. |
|
|
Term
| mechanical advantage of a screw |
|
Definition
| The ideal mechanical advantage of a screw is the length around the threads divided by the length of the screw. |
|
|
Term
| mechanical advantage of a lever |
|
Definition
| The ideal mechanical advantage of a lever is determined by dividing the distance from the fulcrum to the input force by the distance from the fulcrum to the output force. |
|
|
Term
| mechanical advantage of a wheel and axle |
|
Definition
| You can find the ideal mechanical advantage of a wheel and axle by dividing the radius of the wheel by the radius of the axle. |
|
|
Term
| mechanical advantage of a pulley |
|
Definition
| The ideal mechanical advantage of a pulley is equal to the number of sections of rope that support the object. |
|
|
