Recent content by N8G

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    Velocity of a football with and without drag

    That being said, I figured out how to separate the variables but the integrals for part 2 and 3 both turned out to be horrendous given that I’m looking for the velocity wrt height functions. Each integral needed either aggressive attempts at u substitution or partial fraction decomposition...
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    Velocity of a football with and without drag

    Never mind. I think I lost my mind and forgot about how division works. I should be able to just say: mg - cv = mv dv/dy 1 = mv/(mg-cv) dv/dy dy = mv/(mg-cv) dv Sorry for that.
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    Velocity of a football with and without drag

    My bad, any x's should be y's. For the second part of the problem I have: mvdv/dy = mg - cv which I reduce to dv/dy = g/v - c/m From here I don't see a way to isolate the v term on the rhs from the dy when separating my variables. And I am taking g to be -9.8m/s^2
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    Velocity of a football with and without drag

    Homework Statement A professional thrower projects a football straight up in the air. 1. Assuming there is no air drag on the football, find the speed of the football as a function of height as the ball goes up. 2. Assuming the air drag on the football varies linearly with speed, find the speed...
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    E&M: Prove the Divergence Theorem

    Homework Statement Griffiths Introduction to Electrodynamics 4th Edition Example 1.10 Check the divergence theorem using the function: v = y^2 (i) + (2xy + z^2) (j) + (2yz) (k) and a unit cube at the origin. Homework Equations (closed)∫v⋅da = ∫∇⋅vdV The flux of vector v at the boundary of the...
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    Simple Kinematics Problem, unsure of my error

    (v^2)/(2g) = 400/(2*9.81) = approximately 20 Okay awesome. I must've made an egregious calculator error in the beginning. Thank you!
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    Simple Kinematics Problem, unsure of my error

    Yeah, I know that vf = vo +at however that gives me 0 = 20 + (-9.81)t and solving for t gives me a time of 2.039 seconds. However the work that I had already done with energy conservation told me that the max height of the object, that coincides with the point at which its velocity becomes zero...
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    Simple Kinematics Problem, unsure of my error

    Homework Statement Object launched vertically with v initial =20 m/s. No air resistance. How long does it take to reach its max height? Homework Equations 1/2 at^2 + vot = dy .5mv^2=mgh The Attempt at a Solution I began by using conservation of energy to find the max height. .5mv^2 = mgh...
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