Wavelength with P/Q exponent equation-solve for P/Q

AI Thread Summary
The discussion focuses on determining the values of the exponents P and Q in the equation V = Kλ^P g^Q, where V is the velocity of ocean waves, λ is the wavelength, and g is the gravitational field strength. Participants clarify that K is a dimensionless constant and emphasize the importance of dimensional analysis. One user expresses confusion about how to manipulate the exponents to solve for P and Q, considering logarithmic methods. Another user suggests that the problem requires a straightforward dimensional analysis approach rather than logarithmic manipulation. The conversation highlights the need for clarity in solving for the exponents without numerical values, relying solely on the dimensional relationships.
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Homework Statement


Speed of an ocean wave depends on the wavelength \lambda in meters and
gravitational field. (see equation below). Find values of P and Q. K is a constant and has no dimensions


Homework Equations



V = K\lambdaPgQ

The Attempt at a Solution



V=velocity, which is m/s
and i can disregard K because it is a constant which has no dimensions.
g = m/s2
\lambda = m
plugging in the numbers; i get:

m/s = mP(m/s2)Q

here is where i get lost. i don't know how to bring the exponents down so i can solve for it
 
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You have V = K LPgQ
(I used L in place of lambda.)
So LP = V/[K gQ]

To solve for P, take the log of both sides, then divide both sides by log L.

To solve for the other exponent Q, first solve for gQ in a way similar to how I solved for LP, then take the log of both sides, and divide both sides by log g.
 
are you sure? i was workin on this with my prof and he told me not to take the log; that's what i thought of doing initially
and i have no numerical values for the equations; its all dimension analysis
 
OK, what's the exact statement of the problem? As you have it in post 1, it appears that you need to solve for P and Q.
 
The speed of ocean waves depend on their wavelength \Lambda (measured in meters) and the gravitational field strength g (measured in m/s^2) in this way:

v = \LambdaPgQ

where K is a dimensionless constant. Find the values of the exponents P and Q
 
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