# force and mass

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When force force is applied to mass does the mass is set into motion instantaneously

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Unless there's an equal and opposite force to counteract it, then yes.

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what is the case when charged particle is attracted by strong electrostatic field or mass is attracted by another mass

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what is the case when charged particle is attracted by strong electrostatic field or mass is attracted by another mass

I'm not sure exactly what you're asking. Static charges attract (or repel) each other by Coulomb's Law:

$F=\frac{1}{4\pi \epsilon_0}\frac{q_1 q_2}{r^2}$

Similarly, masses attract each other by Newton's Law:

$F=-G \frac{m_1 m_2}{r^2}$

Edited by elfmotat
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Changes propagate at the speed of light.

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i mean that when force acts is there no time needed to overcome the inertial resistence for motion state

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A practical example may be useful: a tennis ball struck by a racquet has a certain dwell time during which the force is being applied but the ball is not moving, but deforming in contact with the racquet.

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A practical example may be useful: a tennis ball struck by a racquet has a certain dwell time during which the force is being applied but the ball is not moving, but deforming in contact with the racquet.

Deformation is motion, though, and if the racquet is moving, the ball is moving, even though there is no relative motion.

However, that does bring up the issue that it does take time for the force to propagate through the object.

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Quick question. Can I do this?

p=F/A. p == pressure, F == force, A == area.

p=(ma)/(V/h)

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P=[(F)<dot>(a_n)]/ A
a_n being the unit normal vector of the area.
so, yeah. you can do that. hmm...What are you going to do with it?
An integral of it?

Edited by Mellinia
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acceleration takes time.

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acceleration takes time.

F=ma

There is no delay inherent in that equation. If there is a force, there is an acceleration.

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A force requires a force carrying particle,which has a field,force increases as the distance decreases?That takes time for a macroscopic effect to be felt?

Edited by derek w
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A force requires a force carrying particle,which has a field,force increases as the distance decreases?That takes time for a macroscopic effect to be felt?

I thought we were discussing classical physics. At the quantum level one generally discusses interactions, with momentum being conserved at certain points in the interaction. Heisenberg's uncertainty principle kinda throws a monkey wrench into the discussion.

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When force force is applied to mass does the mass is set into motion instantaneously

Depends. If the mass is a simple particle or a rigid body the answer is yes. If the body is not rigid then the answer is "no" if the force is by contact. There is a small delay between the application of the contact force and the motion of the centre of mass. The answer is again yes for non-contact forces (e.g. gravity).

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