Recent content by xphysics

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    What is the purpose of the integrand in triple integration?

    Again, I'm not learning from the book, I was just self-teaching through online notes from the one i showed... and i already articulated that I grasped the idea of f(x,y,z) represent density, it's just that if it is.. then the integration usage is completely different compare to single or double...
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    What is the purpose of the integrand in triple integration?

    Hi... So I've been self-teaching Calculus III and I'm currently having a hard time coping with the idea of triple integration. You know how the integrand is f(x,y,z)? isn't that the equation to represent a 4D sketch? because technically, f(x,y,z) is ANOTHER VARIABLE and therefore giving us a 4...
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    Abuse of Notations: Why Is dy/dx Abused?

    Okay, yes a person that agrees with me that dy/dx isn't a formal "fraction" i mean the literal translation of it is "change in y divided by change in x" but that's not it, it's just "the change in y with respect to x." because we are calculating the change infinitesimally. i heard my teacher...
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    Abuse of Notations: Why Is dy/dx Abused?

    but...it's not a fraction?
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    Abuse of Notations: Why Is dy/dx Abused?

    Hey guys, umm I'm just going to get straight to the point, why is the notation of dy/dx for example is being abused so badly? it's not a fraction right? because you can express it in Newtonian notation like y' too! i mean it's just a notation to represent the change in y respect to x I was...
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    Understanding AAPT Hard Problem: Torque & Moment of Inertia Explained

    OH! I GET IT! THANKS DUDE! still kinda not intuitive about the idea of that 15N upward force, what if the shape it different or cutting 2 shapes of different of different size?? is there a mathematical way to determine that 15N?
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    Understanding AAPT Hard Problem: Torque & Moment of Inertia Explained

    Can you explain how you got that? that'd be swelled thanks
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    Understanding AAPT Hard Problem: Torque & Moment of Inertia Explained

    I can't wrap my head around this problem? I think that when you drill a whole like that, the cylinder will roll back to attain its equilibrium so need to hold it with a certain torque to keep it in place, but i do not know how to find the torque What i have in mind is: since T=dL/dt, but L=Iw(w...
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    Projectile Motion Jump Question

    ok it's pretty simple, you set up 2 equations of T(air time) so the first one is t=(vsin(theta))/g and they other one is t=x/(vcos(theta)) set them equal to each other, plug v and x in and find theta, that's it Edit: sry, for the first one just times it by 2 so t=2(whatever is there)
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    Projectile Motion Jump Question

    ummm, i attempted it so basically i used y=1/2at^2. so imagine you're at the peak of 8.9 meters, use that equation to calculate the amount of air time before reaching the air. after that use that t to plug in the vertical kinematic equation: y= y(knot) + v(knot)t - 1/2at^2. plug 8.9 in. For...
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    Calculating Exhausted Mass Velocity in Rocket Thrust Manipulation

    Ahhh I see! You can obtain the velocity of the rocket (at a certain time ofc) then use Tipler's derivation to obtain the exhausted mass velocity. Oh and the reason why I consider the exhausted mass velocity because it affects the velocity greatly IMO if you look at the derivation, same goes for...
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    Calculating Exhausted Mass Velocity in Rocket Thrust Manipulation

    Can you tell me more about the test stand? I thought of enforcing it horizontally and then record it frame by frame to measure how fast the flame is coming out since it's the lost mass( if I'm correct)
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    Calculating Exhausted Mass Velocity in Rocket Thrust Manipulation

    "How would you experimentally calculate..."
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    Calculating Exhausted Mass Velocity in Rocket Thrust Manipulation

    Hey everyone, so I'm just wondering if you guys can articulate the term "velocity of lost mass" from the rocket. After a few massaging on the equations(derivatives and integrals stuff) i found that to manipulate the thrust, one must manipulate the burn rate AND the "velocity of loss mass". all i...
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