Forces and Simple Machines

1. a diagram that shows all the forces acting on an object
4. turning point of a lever
5. force that pushes one object away from another
12. a force that acts on an object without requiring physical contact between the object and the source of the force
13. moves through an object, transferring the downward force into a side ways force
14. push or pull acting on an object
16. balance device consisting of a spring and a scale, used to measure forces in the laboratory
17. two or more forces acting on an object are equal in size but act in opposite directions
19. combination of all forces acting on an object
21. a type of friction caused by air resistance
24. a push or pull that occurs when two objects are touching each other
25. force used to operate a lever

2. used to bridge the gap between high and low surfaces
3. lever that can rotate about its centre, magnifying force or distance
4. a force that opposes the motion of an object
6. a measure of the gravitational pull on an object
7. simple machine with a rope or chain in a groove around its edge that makes it easier to lift an object
8. two or more forces that are unequal in size and direction and therefore change an object's speed, direction or shape
9. a special inclined plane with a thread that wraps around a centre core
10. lever that can change a weak force into a strong force
11. simple machine that reduces the effort needed to do work
15. group of pulleys mounted together in a frame or block, which provides significant mechanical advantage
18. resisting force the effort has to overcome.
20. the attractive force between two masses
22. a push or pull acting on an object
23. unit used to measure force; symbol N