Force and motion are related because exerting force on an object causes a change in motion. An example would be kicking a ball to propel it forward. Two examples of natural forces are gravity and magnetism.
Perhaps the most well known example of the relationship between force and motion is Newton's First Law of Motion. It states that an object at rest or in motion will remain that way unless some type of force is applied.
There are many different types of force that can be applied to an object.
- Normal force - an example of this is a book resting on a table. Gravity holds it there, and the table is exerting force holding it in place.
- Applied force - this refers to when force is used on an object, such as when a person picks up a glass to drink from.
- Frictional force - when two objects come into contact with each other, it causes frictional force. An example is the parts in a motor as they move against each other.
- Tension force - this is a force that pulls equally in both directions. An example is a clothes line that is anchored on each end.
- Spring force - a compressed or stretched spring is an example of this type of force. It can either push or pull an object.
- Resisting forces - this is the force that an effort must overcome to perform work. A leaf blowing in the wind is an example of resistance force.