Forces, energy and power Flashcards
What is friction?
Force which opposes the motion of an object. Acts between two surface in contact
How to increase friction?
Increase surface area
Increase the roughness of surface
How to decrease friction?
Lubricant eg oil
Thin layer of air
What is air resistance?
type of friction force due to air particles coming into contact with an object
If forces act in same direction?
Add together
Newton first law?
An object will remain at rest or move at a constant speed in a straight line unless acted upon by an unbalanced force
Newton Second Law>
F=ma
Newtons Third Law?
for every action there is an equal and opposite reaction
What is tension?
the pulling force of a string or rope
What is free fall?
object experience only force due to gravity acting in on it
What is terminal velocity?
air resistance and weight downwards are equal
What is reaction force?
the upward force due to the scales = reading on the scales
Lift is stationary or constant speed?
R=E balanced forces
Accelerating upwards or decelerating downwards?
F=ma=R-W
Increase in weight
Accelerating downwards or Decelerating upwards?
F=ma+W-R
Decrease in weight
