3.4.1.5 Newton's Laws of Motion Flashcards
What does Newtons First Law State? (Law of Inertia)
An object will remain stationery, or will remain moving with constant velocity, unless a resultant force acts on it.
What does Newton’s First law mean?
A body will stay still or move in a straight line at a constant speed unless a resultant force acts on it.
If the forces acting on a body are not balanced, the overall resultant force will make the body accelerate. This could be a change of speed, direction, or both.
What can we say about an object with constant velocity from this law?
An objected with a constant velocity is either:
Acted on by no forced at all, or the forces acting on it are balanced, so the resultant force is zero.
What does Newtons Second Law state?
The acceleration of an object is directly proportional to the resultant force acting on it.
How can this law be written in equation form?
Resultant Force = Mass x Acceleration
F = m x a
What direction is the acceleration it?
The acceleration is always in the same direction as the resultant force.
What is inertia?
The inertia of an object is its tendency to obey Newton’s first law.
How is the mass of an object a measure of its inertia?
The mass of an object is a measure of its inertia, which is its resistance to change of motion.
More force is needed to give an object a certain acceleration, than to give an object with less mass the same acceleration.
What does Newtons Third Law state?
If an object A exerts a force on object B, then object B exerts an equal and opposite force on object B.
The pairs of forces must always be the same type of force.
