Forces

3. The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not exceeded.
8. A single force on an object that has the same effect as all the original forces acting together.
9. When all the forces acting on an object are balanced.
11. An arrow which represents the size and direction of a force.
15. A device used to measure force.
16. A force of friction produced when an object moves through the air.
18. A force that acts between objects that are physically separated.

1. A force that resists the movement of two surfaces that are sliding (or trying to slide) across each other.
2. The effect of one force is cancelled out by another force leading to a resultant force of zero.
4. An object or group of objects.
5. When the forces applied to an object in opposite directions are not equal in size.
6. The upward force that a fluid exerts on an object floating in it.
7. The force acting on an object due to gravity, measured in newtons (N).
10. The direct affect that one particle or object has on another particle or object.
12. The change in the shape or size of an object.
13. A force of attraction that pulls all things with mass or energy toward one another.
14. The unit for force.
17. A push or pull that acts on an object due to the interaction with another object.