Mechanics Flashcards
When is an object in equillibrium?
When the sum of forces = 0 and the sum of turning moments = 0
What is the center of mass?
The point in a body where the resultant torque due to gravity = 0
What is a couple in terms of forces?
a pair of forces that provide a turning effect but no translational movement. They act in opposite directions, are parallel, but do not act along the same line.
What is terminal speed?
The speed reached when the weight of an object in free fall is balanced by the drag forces acting upwards on an object.
What is drag?
The name given to resistive forces experienced by an object moving through a fluid.
What is newtons first law of motion?
An object will remain in motion, with a constant speed, unless acted on by an unbalanced force.
What is Newtons second law of motion?
An object accelerates in the direction of a resultant force acting on it. F = Ma
What is Newtons third law of motion?
Every force has a paired equal and opposite force. This acts on two objects.
It always acts on 2 separate bodies
They are always the same type of force
They are all of the same magnitude
They act along the same line
What is an elastic and inelastic collision?
An elastic collision - kinetic energy is conserved
Inelastic - Kinetic energy is not conserved
