Solving Mechanics Queries: Q1-Q3

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In mechanics, when a force is applied to an object, it accelerates according to the equation F=ma, but the object itself does not become a force. The normal force arises from the interaction between two surfaces in contact, primarily acting as the ground's reaction to the weight of an object, and is not simply a reaction force to gravity. For a block in motion colliding with another, analyzing the situation through conservation of momentum and energy is more effective than focusing solely on forces and accelerations. Tension in a string occurs due to the forces acting on the objects connected by the string, and for numerical practice, Irodov's problems are recommended. Understanding these concepts is crucial for mastering mechanics.
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Q1-if i apply a force on an object that object moves with acceleration does it mean object becomes like a force f=ma ?
Q2-is normal force a reaction to action of weight,since a force G.F acting on me so i must accelerate and mass*acc.=force so i am acting force on a floor(say) ,OR normal force is a force when two surfaces are in contact each one is acting a force on other and normal force is one of this force.
Q3-block1 is accelerating due to action of external force when it hits another block2, forces on block 2 are force due to block1 it was accelerating and m*a=f and contact force because for short period of time two surfaces will be in contact?
PLEASE HELP ME I AM HAVING TROUBLE UNDERSTANDING MECHANIC
 
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Q1: The object experiences a force according to f=ma, it does not become a force. It can exert a force on another object if it bumps into it later on.

Q2: Normal force typically refers to two rigid objects in contact and not in motion relative to each other in the direction normal to the surface where they contact. What gives rise to the normal force could be anything but in textbooks they usually mean it as the ground pushing up on an object as gravity pulls it down (This is not the reaction force. The reaction force of Earth's gravity pulling me down is my gravity pulling the Earth up.) The ground's normal force is ultimately electromagnetic forces binding the molecules of the ground together. Also, don't forget that the F in the equation F = ma is the total of all forces acting on the body with mass m. So a block sitting motionless on the ground has a = 0 and therefore F = 0 because the normal forces cancels out gravity.

Q3: For collisions of free bodies, you are better off using conservation of momentum and conservation of energy than forces/accelerations
 
Thankkkkkkkkkkkkksssss buddy one more thing how a tension in a string occur and for numerical practice WILL i.e irodov will be best
best wishes from india
 
I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...
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