Newton's First Law
Newton's First Law of motion predicts the behaviour of objects for which all existing forces are balanced.
The First Law states that objects with balanced forceWhen the total force in opposite directions are equal in magnitude. For example, with a thrust of 15 N and a frictional force of 15 N, the body experiences balanced forces. acting on them will stay at restA stationary object which has a speed of zero. For example, the bus started from rest before it reached a speed of 8 m s-1., or in constant motion.
Newton discovered that objects will continue to do what they are doing until a net, or unbalanced force, acts on the object.
From this we can determine that:
- forces act on objects
- forces cause changes
We can also determine that forces acting on an object can change:
- the shape of the object
- the speed of the object
- the directionInformation to give the direction of travel, or the direction of a force, for example, a speed of 20 m s-1 to the left, or a force of 15 N to the right. in which the object is moving