Does it matter if one uses gauge instead of absolute pressures in applying Bernoulli's equation? Explain.

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(N/A) No,it does not matter if one uses gauge pressure instead of absolute pressure while applying Bernoulli's equation. Bernoulli's equation is given by $P_1 + \frac{1}{2}\rho v_1^2 + \rho gh_1 = P_2 + \frac{1}{2}\rho v_2^2 + \rho gh_2$. If we use gauge pressure,we replace $P$ with $P_{gauge} = P_{abs} - P_{atm}$. Substituting this into the equation,the atmospheric pressure $P_{atm}$ appears on both sides of the equation and cancels out. Therefore,the choice of pressure scale does not affect the result,provided that the atmospheric pressure is the same at both points.

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