Chapter 3- Dynamics Flashcards
Define mass
Mass is a measure of the amount of matter in a body (or object)
Define gravitational field
Gravitational field is a region in which mass experiences a force due to gravitational attraction
Define Gravitational field strength
Gravitational field strength is the force acting on a unit mass
Difference between mass and weight
Mass is measure of the amount of substance in a body while weight is due to the gravitational force acting on a body
Mass is a scalar while weight is a vector
Mass is constant regardless of gravitational field strength while weight varies according to the gravitational field strength
State Newton’s first law of motion
An object at rest will remain at rest and an objection motion will continue in motion at constant speed in a straight line unless a resultant force acts on it
Define inertia
The inertia of a body is its tendency to continue with its state of rest or motion. The mass of the body is a measure of its inertia. The greater the mass, the greater its inertia
State Newton’s second law of motion
The resultant force acting upon an object is equal to the product of the mass and the acceleration of the object; the direction of the force is the same as that of the acceleration
Explain terminal velocity
When an object falls vertically through air, the upward resistive force (air resistance or drag force) acting on it increases as the velocity of the object increases
Eventually when the downward force of gravity on the object is equal to the upward resistive force, the object will fall with terminal velocity. This is the constant maximum velocity of the object
State Newton’s third law of motion
The force which body A exerts in body B is always equal in magnitude and opposite in direction to the force which body B exerts on body A
Define force
A force is defined as an influence which changes or tries to change the state of motion, shape or size of a body
