Recent content by tjosan

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    I Calculate new height of truncated cone

    I think I solved it. The ratio, C, between the H and R-r must remain the same for the new cone (because the angle is the same, tan (angle) = constant) , so C = H/(R-r) = H1/(R-r1) => H1=C*(R-r1) [1] V1=1/3*pi*H1*(R^2+R*r1+r1^2) = 1/3*pi*C*(R-r1)*(R^2+R*r1+r1^2), where r1 is the new upper...
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    I Calculate new height of truncated cone

    Hi, Suppose you have a truncated cone filled water with the lower radius being R, and upper r (R>r), and the height is H. R, r and H is known so the volume, V, can be calculated using V=1/3*pi*H*(R^2+R*r+r^2). Now suppose you remove some water so that you end up with a lower volume, V1. The...
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    I Temperature change due to mixing liquids, heating and heat losses

    I just did the algebra and arrived at the same result, thanks! Although I only used ##\dot{Q}## in ##T_\infty##, and not ##\dot{Q}(GC+hA)##, which I assume was a mistake.
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    I Temperature change due to mixing liquids, heating and heat losses

    The solution is far from pretty :) https://www.wolframalpha.com/input?i=%28m%2BG*t%29*C*dT%2Fdt%3DGC%28T_0-T%29%2BQ-h*A*%28T-T_1%29%2C+T%280%29%3D56
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    I Temperature change due to mixing liquids, heating and heat losses

    Thank you very much. I don't have a word-to-word statement, as this problem is an invention of my own. :)
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    I Temperature change due to mixing liquids, heating and heat losses

    Hello, I am stuck how to proceed with the equations below. The problem: A tank containing ##m_0## mass, with a temperature of ##T_0##, is to be filled with a total mass of ##m_1##, with the constant mass flow rate ##G## and temperature ##T_1## during ##t_p## seconds. ##T_0>T_1##. Other than the...
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    Force on submerged plate perpendicular to flow

    Hey, I wonder how I can calculate the force of a plate that is submerged in water. I thought maybe the drag equation would be suitable for this with the drag coefficient set to 1.28 (https://www.grc.nasa.gov/www/k-12/airplane/shaped.html). But is implies the flow is according to the image...
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    I How do you calculate the probability without using the complement?

    Thank you for the replies. I merely wanted to understand why the complement is used by seeing the actual implications of not using it. I already knew you could count all the possibilities which is why I asked for an analytical approach. I did not have any expections of it being easy though...
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    I How do you calculate the probability without using the complement?

    "Anakin, if one is to understand the great mystery, one must study all its aspects, not just the dogmatic narrow view of the Jedi." /Palpatine @etotheipi & @fresh_42: thanks for the help 🙂
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    I How do you calculate the probability without using the complement?

    Well yes. But say I have 100000 dice. Would take a while to sum up all the positive constellations then. Isn't there any... Well analytical ways of doing this? Edit: basically I am trying to find a way to end up with equation like this (sqrt(11)/6)^2 somehow.
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    I How do you calculate the probability without using the complement?

    Let's say I'd like to calculate the probability of getting at least one 4 when rolling two dice. That's 1 minus the probability of not getting any 4, i.e 1 minus the complement, 1-(5/6)^2. But how would I calculate without using the complement?
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    Slab resting on two supports: Maximum weight added without tipping?

    Would it requie more or less weight if W1 was placed on the corner of the slab? Is it dependant on the width?
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    Slab resting on two supports: Maximum weight added without tipping?

    Thank you. Yeah, made a mistake and wrote it as a force. Are you saying it should be: WA * g * A/2 + W1 * g * A ? What I did on the left side, or what I tried to do, was to add the extra lever distance resulting from the weight W1, by calcuting the ratio of W1 to W1+WA and adding it to A/2...
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    Slab resting on two supports: Maximum weight added without tipping?

    Hi, My attempted solution is in the image: I choose the edge on the left side, but the solution should be similar on both sides (just substitute C for A). (I missed to multiply by "g" in F_2.) Is this the correct way of thinking? I'm not sure about the distance "D".
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    Weight measurements and gravitational acceleration

    Thank you. Didn't distinguish between scale/balance and mass/weight. But now it makes sense :)
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