Recent content by yy205001

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?

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...

The pressure is 100kPa in state1 but did not mention about the pressure about state2?

Can I assume the pressure is constant during the process?

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...

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!

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...

Thank you so much!

Hallsoflvy: oh yeah! So sqrt(2)-n→0 as n→∞!?

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.

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...

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?

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...

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...

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?