a)F = ma
F = dp/dtc)P = mv
d)dp = Ft
Here F=force, m= mass, a= acceleration, p= momentum, v= velocity, t= time
I don't have even the faintest of idea about this question.Please help.
# Which of the following relations is not valid according to theory of relativity:
a)F = ma
F = dp/dt
c)P = mv
d)dp = Ft
Here F=force, m= mass, a= acceleration, p= momentum, v= velocity, t= time
I don't have even the faintest of idea about this question.Please help.
a)F = ma
F = dp/dtc)P = mv
d)dp = Ft
Here F=force, m= mass, a= acceleration, p= momentum, v= velocity, t= time
I don't have even the faintest of idea about this question.Please help.
QUOTE (plasma+Aug 2 2006, 06:58 PM)
# Which of the following relations is not valid according to theory of relativity:
a ) F = ma
b ) F = dp/dt
c ) P = mv
d ) dp = Ft
Here F=force, m= mass, a= acceleration, p= momentum, v= velocity, t= time
I don't have even the faintest of idea about this question.Please help.
Mr. Homm will back me up with the best results, but the solution is to know the relativistic expressions and find the equations that don't match.
For example, ( c ) should be written as p = gamma m v in SR, so ( c ) is not valid.
And ( a ) is F = gamma m (1 + gamma^2 v transpose(v) ) a in SR (F, force, is not always parallel to a, acceleration)
so ( a ) is not valid.
http://math.ucr.edu/home/baez/physics/Rela...ty/SR/mass.html
( b ) should be in your textbook, and it is valid. (provided F, p and t are all in the same frame)
( d ) looks like ( b ) but this could be a side effect of your writing it on the web.
a ) F = ma
b ) F = dp/dt
c ) P = mv
d ) dp = Ft
Here F=force, m= mass, a= acceleration, p= momentum, v= velocity, t= time
I don't have even the faintest of idea about this question.Please help.
Mr. Homm will back me up with the best results, but the solution is to know the relativistic expressions and find the equations that don't match.
For example, ( c ) should be written as p = gamma m v in SR, so ( c ) is not valid.
And ( a ) is F = gamma m (1 + gamma^2 v transpose(v) ) a in SR (F, force, is not always parallel to a, acceleration)
so ( a ) is not valid.
http://math.ucr.edu/home/baez/physics/Rela...ty/SR/mass.html
( b ) should be in your textbook, and it is valid. (provided F, p and t are all in the same frame)
( d ) looks like ( b ) but this could be a side effect of your writing it on the web.
Answer A is not valid. The others are correct for relativity, provided you remember that some people write m to mean the mass AFTER the relativistic mass increase, and m_0 to mean the rest mass.
F = dp/dt is correct, and p = mv is correct , but p = m_0v would not be correct. So answer C is correct if you interpret m as m = gamma*m_0.
I agree with rpenner that D looks like just another copy of B, although I would expect to see Fdt instead of Ft.
A is not valid because both mass and velocity change when force is applied, so f = dp/dt = d/dt(mv) = m*dv/dt + v*dm/dt = ma + v*dm/dt. So basically the product rule from differential calculus shows that there is something besides ma in the formula.
Hope this helps!
--Stuart Anderson
F = dp/dt is correct, and p = mv is correct , but p = m_0v would not be correct. So answer C is correct if you interpret m as m = gamma*m_0.
I agree with rpenner that D looks like just another copy of B, although I would expect to see Fdt instead of Ft.
A is not valid because both mass and velocity change when force is applied, so f = dp/dt = d/dt(mv) = m*dv/dt + v*dm/dt = ma + v*dm/dt. So basically the product rule from differential calculus shows that there is something besides ma in the formula.
Hope this helps!
--Stuart Anderson
Thanks for the detailed explanation.
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