How Does the Speed Distribution Function Determine Vmin and Vmax?

AI Thread Summary
The discussion centers on determining the minimum speed (Vmin) and maximum speed (Vmax) from the given speed distribution function f(V) = AV(B - V)/B^3. Participants debate the relationship between maximum speed and average speed, with one suggesting they are equal, which is incorrect as it implies uniform particle speed. The minimum speed is identified as the point where f(V) approaches zero, but the exact value cannot be determined without knowing constants A and B. The maximum speed is linked to the rate of change of the distribution function with respect to speed. Overall, the conversation emphasizes the need for a deeper understanding of the distribution function to accurately identify Vmin and Vmax.
reactor
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Dear
I have problem with determine the minimum speed in this problem , I think the the maximum speed equal to the average speed and the most probable speed can be obtain by derive equation and equally to zero .Is my solution correct?

The speed distribution function for N particles in a fixed volume is given by f (V) = AV(B - V)/B^3,
where V (>0) is the particle speed, and A and B are positive constants. Determine:
(a) The minimum speed Vmin and maximum speed Vmax.
b) The most probable speed where the probability density function is the largest.
 
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I think the the maximum speed equal to the average speed
If that would be true, all particles would have to have the same speed.

I have problem with determine the minimum speed in this problem
What is the minimal V where f(V) is not zero?
If you don't see that, make a sketch of f(V).

and the most probable speed can be obtain by derive equation and equally to zero
Right.
 
mfb said:
If that would be true, all particles would have to have the same speed.

What is the minimal V where f(V) is not zero?
If you don't see that, make a sketch of f(V).

Right.

the minimum when B=v=0 and what about the maximum
 
the minimum when B=v=0
Why B=?
A and B are parameters, you cannot set their values.

and what about the maximum
Did you draw the sketch I proposed? Do you see the maximum?
 
reactor said:
Dear
I have problem with determine the minimum speed in this problem , I think the the maximum speed equal to the average speed and the most probable speed can be obtain by derive equation and equally to zero .Is my solution correct?

The speed distribution function for N particles in a fixed volume is given by f (V) = AV(B - V)/B^3,
where V (>0) is the particle speed, and A and B are positive constants. Determine:
(a) The minimum speed Vmin and maximum speed Vmax.
b) The most probable speed where the probability density function is the largest.
First of all, this is not a Maxwellian distribution. The distribution is determined by this equation.

The minimum speed is the speed for which the distribution f(V) < 1. Since we don't know the values of A and B you cannot really determine that so assume it is very close to f(V) = 0.

How is the maximum related to the rate of change of f(V) with respect to V?

AM
 
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