if i forget the principle of superposition one more time i will never forgive myself

velocity

rate of change of displacement with respect to time

acceleration

a rate of increase of velocity with respect to time

conditions for equilibrium

the resultant force in any direction is 0
the resultant torque about any axis is 0

upthrust

due to the pressure difference between the top and bottom surfaces of the fluid, a body partially or fully submerged in said fluid will experience an upward force

Hooke's law

the extension of a body is proportional to the applied load/force, provided the limit of proportionality is not exceeded
[F = kx , lim of proportionality not exceeded]

moment of a force

(about a pivot) is the product of the force and the perpendicular distance of the line of action of the force from the pivot
[M = Fd, d = //dist from line of action of force to pivot]

principle of moments

For an object to be in rotational equilibrium, sum of clockwise moments about any point must be equal to the sum of anticlockwise moments about said point
[at any pt, ACM=CM]

linear momentum

(of a moving body) product of its mass and linear velocity

newton's 1st bby

every body continues in its state of rest, or motion with uniform velocity, unless acted on by a resultant force

newton's 2nd bby

rate of change of momentum of a body is directly proportional to the force acting on it, if said change takes place in the direction of the resultant force

newton's 3rd bby

if body A exerts a force on body B, body B will exert a force on body A that is of the same kind, equal in magnitude and opposite in direction

impulse

product of the force and the time during which the force acts