Elastic Object : When an applied force is removed from an object, the ability to return to its original form is called an elastic object
Hooke's Law : As long as the elastic limit of a body is not exceeded, the extension is directly proportional to its applied force.
F = kx
When object is at rest, there are only 2 forces.
Weight (gravitational force)
normal reaction force
If that is unbalanced force, the object will start to move or speeding up or slowing down.
So, that is acceleration.
When object is moving, there are 4 forces.
Weight (gravitational force)
normal reaction force
air resistance friction (Drag)
forward force by object (thrust)
Acceleration of free fall(g) for an object near to the Earth, this is approximately constant and is approximately 9.8m/sxs
The air resistance to a light body is large when compared with the body’s weight.
All bodies falling freely under the force of gravity do so with uniform acceleration if air resistance is negligible
In calculations using the equations of motion, g replaces a. It is given a positive sign for falling bodies and a negative sign for rising bodies since they are decelerating
