Recent content by yy205001

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    Bernoulli equation - pitot tubes

    but isn't that P only the static pressure? But in this case we also have to include the dynamics pressure as well, so the total pressure P+(p/2)V2 stay the same everywhere on the streamline?
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    Bernoulli equation - pitot tubes

    Homework Statement Homework Equations P1+pV12/2+pgh1=P2+pV22/2+pgh2 The Attempt at a Solution My thinking: since the pitot tubes measure the stagnation pressure (static + dynamics pressure) and the height of the tubes are the same. By Bernoulli's equation, the total pressure along a...
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    Thermodynamics of heating water in a cylinder with piston

    The pressure is 100kPa in state1 but did not mention about the pressure about state2?
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    Thermodynamics of heating water in a cylinder with piston

    Can I assume the pressure is constant during the process?
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    Thermodynamics of heating water in a cylinder with piston

    Homework Statement Consider water contained in a cylinder at 25C with a frictionless piston with some weights on it. Initially the pressure inside the piston is 100kPa and then the water is heated such that the water does 290kJ/kg of work on the piston. Find the final temperature of the...
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    Elastic moduli of metals and polymers

    Why is there such a large difference between the elastic moduli of metals and polymers? Is it because of different bonding? Or something do with the structure? Thank you!
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    Materials - Modulus of polymer and metal

    Homework Statement Why is there such a large difference between the elastic moduli of metals and polymers? Homework Equations The Attempt at a Solution I am thinking because of the different bonding between metals and polymers. Since metals have metallic bonding and polymers...
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    Convergence of Complex Sequences at Infinity

    Thank you so much!
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    Convergence of Complex Sequences at Infinity

    Hallsoflvy: oh yeah! So sqrt(2)-n→0 as n→∞!?
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    Convergence of Complex Sequences at Infinity

    mfb: But when the minus is there, the value is still varying, it does not go to infinity in denominator for part a. So I still cannot get the limit equal to 0.
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    Convergence of Complex Sequences at Infinity

    Homework Statement a) (1+i)-n as n→∞ b) n/(1+i)n as n→∞ Homework Equations The Attempt at a Solution My answers were divergent for both question because (1+i)n=sqrt(2)*en*pi*i/4, so when n→∞, the limit is varying on the circle with radius sqrt(2). But the solution said both of...
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    Complex analysis - partial fraction expansion

    From my notes, i found that Ʃ(-1)nf(n) (from -∞ to ∞) = - Ʃ Res(pi*csc(pi*z), zj) (poles zj of f(z)). So, should I let f(n) = 1/(n2+a2) in this case?
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    Complex analysis - partial fraction expansion

    Homework Statement Show that: Ʃ(-1)n/(n^2+a^2) (from n=0 to ∞) = pi/[asinh(pi*a)], a\neq in, n\in Z. Homework Equations f(z) = f(0) + Ʃbn(1/(z-an)+1/an) (from n=1 to ∞) , where bn is the residue of f(z) at an. The Attempt at a Solution The main problem is I don't how to pick the...
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    Can the Laplace Transform Be Determined for Specific Functions?

    vela: I think I wrote something wrong above, it should be abs(f(t)) ≤ K*eσt. So, if there exist real constants K and σ such that for all sufficiently large values of t, the inequality holds then Laplace transform exists. PhysicsandSuch: I think the convolution integral equation might help...
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    Can the Laplace Transform Be Determined for Specific Functions?

    vela: But when happen if t4<1? Then K=1 does not satisfy the inequality. PhysicsandSuch: So i need to make assumption for Question 2?