Simple Machines

3. A short,sharp-pointed metal pin with a raised helical thread running around it and a slotted head, used to join things together by being rotated so that it pierces wood or other material and is held tightly in place
5. A piece of metal,etc. having one thick end and tapering to a thin edge, that is driven between two objects or parts of an object to secure or separate them
7. The ratio of the force produced by a machine to the force applied to it, used in assessing the performance of a machine
10. Strength,energy as an attribute of physical action or movement
11. A wheel with a grooved rim around which a cord passes, which acts to change the direction of a force applied to the cord and is used to raise heavy weights

1. A circular object that revolves on an axle and is fixed below a vehicle or other object to enable it to move over the ground
2. A sloping ramp up which heavy loads can be raised by ropes or chains
4. A thing made,adapted for a particular purpose, especially a piece of mechanical or electronic equipment
6. The resistance that one surface or object encounters when moving over another
8. A rod or spindle passing through the centre of a wheel or group of wheels
9. The force that attracts a body towards the centre of the earth, or towards any other physical body having mass
12. A rigid bar resting on a pivot, used to move a heavy or firmly fixed load with one end when pressure is applied to the other