Solving Physics Equation for v: Mistakes and Solutions

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The discussion focuses on solving a physics equation for the variable v, where the user struggles to arrive at the correct answer of 42. The main mistake identified is the failure to multiply the first term on the right-hand side by v^2 during the algebraic manipulation. Additionally, there is a shift in the conversation towards the Continuity Equation and its role in explaining how jet engines generate thrust, indicating a need for a comprehensive understanding of the underlying physics principles. The user seeks specific explanations to clarify these concepts. The thread highlights the importance of careful algebraic manipulation and the connection between physics equations and real-world applications.
Warwick
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Okay, I have this equation and I want to solve for v, so basicaly it's really just an algebra problem.

Original equation
20=(v)sin(35)*(159/v)+.5(-9.8)(159/v)^2

v^2=(sin(35)(159)+.5(-9.8)(159^2))/20<-- what I do, then I take it to the ^(1/2)

The answer should be 42, but I keep getting crazy answeres. What am I doing wrong?

thanks
 
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When you multiplied through by v^2, you forgot to multiply the 1st term on the RHS by v^2.

Claude.
 
Can anyone help me with this question?

Use the Continuity Equation to explain how jet engines provide a forward thrust for an airplane.

I don't think only the actual equation would help to explain fully the question but I really need some specific explanation for this.
 

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