Forces, accelerations and Newton's Laws of motion

What is Newtons first law and what does this mean ?

Newtons first law says that the velocity, speed or direction of an object will only change if a resultant force is acting on it.

This means that :

• If the resultant force on a stationary object is zero the object will remain stationary

• If the resultant force on a moving object is zero then it will continue to move at the same velocity in a straight line.

• If the resultant force on an object is not zero its velocity will change

What is Inertia ?

The tendency of an object to remain in a steady state

What is newtons second law ?

Acceleration is directly proportional to the resultant force of an object but inversely proportional to the mass of a object

What is inertial mass ?

A measure of how difficult it is to change the velocity of a object