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ehrenfest
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[SOLVED] Newton's third law
My book gives two forms of Newton's Third Law:
Weak Form: The forces exerted by two particles [itex]\alpha[/itex] and [itex]\beta[/itex] on each other are equal in magnitude and opposite in direction
Strong Form: The forces exerted by two particles [itex]\alpha[/itex] and [itex]\beta[/itex] on each other, in addition to being equal and oppositive, must lie on the straight line joining the two particles.
Here are my questions:
1) Is it true that there are cases IN WHICH BOTH THE STRONG FORM AND THE WEAK FORM FAIL TO HOLD?
2) My book says that for example, magnetic forces, those forces exerted on a moving charge q in a magnetic field [itex]\mathbf{B}[/itex] [itex](\mathbf{F}=\mathbf{q}v \times \mathbf{B})[/itex], obey the weak form, but not the strong form. I don't understand why that obeys the weak form. What are the two particles?
Homework Statement
My book gives two forms of Newton's Third Law:
Weak Form: The forces exerted by two particles [itex]\alpha[/itex] and [itex]\beta[/itex] on each other are equal in magnitude and opposite in direction
Strong Form: The forces exerted by two particles [itex]\alpha[/itex] and [itex]\beta[/itex] on each other, in addition to being equal and oppositive, must lie on the straight line joining the two particles.
Here are my questions:
1) Is it true that there are cases IN WHICH BOTH THE STRONG FORM AND THE WEAK FORM FAIL TO HOLD?
2) My book says that for example, magnetic forces, those forces exerted on a moving charge q in a magnetic field [itex]\mathbf{B}[/itex] [itex](\mathbf{F}=\mathbf{q}v \times \mathbf{B})[/itex], obey the weak form, but not the strong form. I don't understand why that obeys the weak form. What are the two particles?
Homework Equations
The Attempt at a Solution
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