Even monkeys fall from trees

Newton's Second Law: F = ma. (the vector sum of the forces F on an object is equal to the mass m of that object multiplied by the acceleration vector a of the object)

The monkey is not moving, and thus not accelerating, therefore the total (net) force on the monkey is zero. The only force acting upwards in this model is the force from the branch. The only force acting downwards is the force from the effects of gravity (gravity is not a force). These forces must be equal and opposite.

Forces acting on the monkey: -Gravitational Force (Downward) -Normal Force (Upward by branch)

When about to fall, acceleration is zero. Net External Force=0

N-Mg=0(no acc.)

which implies

N=Mg

Newton's First Law : In an Inertial Frame of reference , A body stays at rest or in uniform motion unless acted upon by an External Force.Here clearly the body is not in uniform motion and is in the state of momentary rest , therefore the vector sum of forces acting on the body is equal to zero.

Here there are mainly two forces acting on the body :

1 . Force of gravity on the 'Monkey' (downwards)

2 . Electromagnetic Force by the 'Branch on the Monkey'(upwards)

Therefore since the vector sum of all the forces is zero ;

Force of gravity ( j ) + Electromagnetic Force ( -j ) = 0

Force of gravity = Electromagnetic Force

In the mention situation still gravity hasn't overcome the weight.The net force of the system is zero.by system i mean the weight of the monkey and force of gravity. mathematically, summation of the forces equal to zero f=ma=0 if "f" is the net force.

Mechanical equilibrium:

In order for monkey to remain motionless (neglect swinging), the net force acting upon the monkey must be zero. The down force is gravity, the up force is the branch. Right before the fall, since the branch is about to give up, and the monkey is almost still, the two forces are about equal.

Newton's Third Law: every action has an equal but opposite reaction. Force of the branch must be equal to the force of gravity.