Newton's first law
According to Newton's first law of motion, an object remains in the same state of motion unless a The single force that could replace all the forces acting on an object, found by adding these together. If all the forces are balanced, the resultant force is zero. acts on it. If the resultant force on an object is zero, this means:
- a stationary object stays stationary
- a moving object continues to move at the same The speed of an object in a particular direction.
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Resultant forces
Two forces can be added together to find a resultant force. The resultant force is a single force that has the same effect as two or more forces acting together.
Two forces in the same direction
The resultant force of two forces that act in the same direction can easily be calculated - to do this, just add the The size or severity of something. For example, an earthquake. of the two forces together.
Example
Two forces, 3 newtons (N) and 2 newtons (N), act to the right. Calculate the resultant force.
3 N + 2 N = 5 N to the right
Two forces in opposite directions
Two forces that act in opposite directions produce a resultant force that is smaller than either individual force. It is often easiest to subtract the magnitude of the smaller force from the magnitude of the larger force.
Example
A force of 5 N acts to the right, and a force of 3 N acts to the left. Calculate the resultant force.
5 N - 3 N = 2 N to the right
Inertia - Higher
The tendency of an object to continue in its current state (at rest or in uniform motion) is called The tendency of an object to continue in its current state (at rest or in uniform motion) unless acted on by a resultant force.. Inertial mass is defined as the ratio of force over acceleration. Inertial mass is a measure of how difficult it is to change the velocity of an object.
