Mechanics midterm-terminal velocity question

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The discussion revolves around calculating the terminal velocity of a boy sliding down a water slide, considering both kinetic friction and water resistance. The user has derived an equation involving gravitational force, friction, and water resistance but is unsure about the integration process to find terminal velocity. Clarification is provided that the friction force should be distinguished from the gravitational force component acting down the slide. The conversation emphasizes the need to correctly account for both forces in the calculations. The user seeks assistance to complete the integration and determine the terminal velocity accurately.
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1. A boy is sliding on the water sliding bed. The angle between sliding bed and the horizontal is θ(theta). When the coefficient of the kinetic friction is μ(COF) and when the wate resistance is F(v)=-cv, obtain the terminal velocity. (two frictions - for this i don't know whether it means linear friction+quadratic friction or something else)



3. But anyway, so far I reached this point:

F-force due to gravity
F(v) - force due to water resistance

F*μ+F(v)=mdv/dt

-mgsin(θ)μ-cv=mdv/dt

dt=mdv/mgsin(θ)μ -cv

And I'm stuck right here. Are my workings so far correct? Can you show me how to integrate this function and find terminal velocity. I know it's going to have exponential term which will drop to zero after sufficient time.
 
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Welcome to PF!

Hi Kara-Mustafa!Welcome to PF! :smile:

You're confusing the friction (µN) with the downhill component of the gravitational force …

you need both :wink:
 
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