Mechanics : Newton's Laws Flashcards
Scalar
A physical quantity that can be described by a single number using its size.
Vector
A physical quantity that has both magnitude and direction.
Resultant (FNET)
The vector sum of two or more vectors
OR
A single vector having the same effect as two or more vectors together.
Perpendicular vectors
Vectors that are at right angles to each other
Co-linear vectors
Vectors that act in one dimension
Component of a Vector
Effect of a vector in a certain direction.
Components of a vector
Vectors that together have the same effect as the original vector.
Net component
Combined effect of components in a certain direction
Resolve into components
Determine the components of a vector
Equilibrant
The force that keeps a system in equilibrium.
(Resultant = 0)
Normal Force
The force or the compound of a force which a surface exerts on an object with which it is in contact, and which is perpendicular to the surface
Frictional force
The force that opposes the motion of an object and which acts parallel to the surface.
Static frictional force
The force that opposes the tendency of motion of a stationary object relative to a surface.
Coefficient of static friction
The ratio of the maximum static friction force to the normal force.
Kinetic frictional force
The force that opposes the motion of a moving object relative to a surface.
Coefficient of Kinetic friction
The ratio of the kinetic friction force to the normal force.
Newton’s first law of motion
A body will remain in its state of rest or motion at constant velocity unless a non-zero resultant/ net force acts on it.
Inertia
The resistance of an object to any change in its state of motion. The mass of an object is a quantitative measure of its inertia.
Newton’s second law of motion
When a non-zero resultant/ net force acts on an object, the object will accelerate in the direction of the force at an acceleration directly proportional to the force and inversely proportional to the mass of the object.
Newton’s third law of motion
When object A exerts a force on object B, object B simultaneously exerts an oppositely directed force of equal magnitude on object A.
Newton’s law of universal gravitation
Each body in the universe attracts every other body with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres.
mass
The amount of matter in a body measured in kilogram (kg)
Weight
The gravitational force the Earth exerts on any object on or near its surface.
Weightlessness
The sensation experienced when all contact forces are removed.
ie. no external objects touch one’s body.
