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

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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
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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