hi eagle so what u r sayin is that weight does not exert any
downwards force but when it hits someyhing the reason y it hurts is
because there is a net force downeards of contct force on the hand?
so there is always a net downwards force when its on something?
lastly is that contact force the same aa weight i think it is as
weight is countered by contact force on the liad itself n there is
one contact force on the ground so if weight was gone it would be a
3rd law case n the object will fly up so is that true? eagle is
this the correct working taking the object to be 10kg.
F weight=10x10=100N F contact:=100N
so all the forces on the object would be weight and contact
force on hand is contact force on it
so is the reason on y it falls unlike earth the hand is a
movable object and thus it move down with a force of 100N which qas
exerted by contact force on the hand by the book. as its a third
law case as now its 2 objects. the objects are the hand and the
book but because the cointact force on the book is cancelled
out by the weight so there is a net force downwards by
contact force from book on hand?
No, weight exerts a downward force.
But if an object on a table is stationary, then a upwards
contact force (with magnitude equal to weight) has to be applied to
the object by the table, so as to make resultant force = 0.
By newton's third law, because there is a force by the table on
the object, there is also a force on the table by the object.
F weight=10x10=100N F contact:=100N
so all the forces on the object would be weight and contact
force on hand is contact force on it
When in equilibrium, yes. This is correct.
so is the reason on y it falls unlike earth the hand is a
movable object and thus it move down with a force of 100N which qas
exerted by contact force on the hand by the book. as its a third
law case as now its 2 objects. the objects are the hand and the
book but because the cointact force on the book is cancelled
out by the weight so there is a net force downwards by
contact force from book on hand?
I think you need to improve on your English. Not very sure what
you mean here.
The reason why things fall at increasing speed is either due to
zero upwards force or an upwards force that is much smaller than
its weight. This results in a resultant downwards force, and hence
things accelerates downwards.
However, things can still fall at constant speed (terminal
velocity) with downwards force (weight) equals to upwards force
(air resistance). There is zero resultant force here. The upwards
force of the air on the falling object equals to the downwards
force of the falling object on the air (Newton's third law).
The key point here to take note is resultant
force. Only with a resultant force would you have
acceleration (Newton's 2nd Law). With zero resultant force, you
have zero acceleration (Newton's 2nd Law). As a result, objects
would either remain stationary or continue in the same velocity as
before (Newton's 1st law).
