# Search results

1. ### Circuit diagram question

Homework Statement I am trying to find the current across Rg. I do not understand the answer provided Homework Equations The Attempt at a Solution Am I supposed to add the two voltage sources and then continue?
2. ### Help with view factors

Homework Statement I found the values ##F_{3\rightarrow(1+2)}=0.32## and ##F_{1\rightarrow3}=0.25## I now want to find ##F_{2\rightarrow3}## Homework Equations Reciprocity relation ##A_iF_{i\rightarrow j}=A_jF_{j\rightarrow i}## The Attempt at a Solution Using the reciprocity relation to find...
3. ### How to find peak time?

Homework Statement I am trying to find the peak time and %OS from the diagram Homework Equations The Attempt at a Solution I know how to get the %OS but for the peak time, isn't it just the time of the first peak, so around 1.1s? But the answer I am supposed to be getting is 0.0922s
4. ### Velocity diagram for a rotating blade

Homework Statement http://postimg.org/image/5o9kcuj57/ I do not understand what the vectors W and V represent Homework Equations The Attempt at a Solution I know U is the tip speed velocity but I don't know about the other two
5. ### Help on simplifying block diagram

Homework Statement I am trying to understand the simplification between these two block diagrams Homework Equations The Attempt at a Solution I understand the 2s+1/s has been moved past the summing junction, resulting in the 2s. But I dont understand where the s/2s+1 block comes from
6. ### Number of linearly independant motions

Homework Statement http://postimg.org/image/uc0c581cb/ For (b), how many points of linearly independent motion are present in this system? Homework Equations The Attempt at a Solution The solution says there is rotation of J1, between K1 and D1, to the right of K2 and finally J3 But isn't...
7. ### Engineering Introductory book for mechanics of machines?

Topics covered include links, mechanisms, Kinematics of rigid bodies : Relative Velocity and Acceleration method, Instantaneous Centre Method, Dynamics of Rigid Links, Gears, Cams etc I cuurently have this book ...
8. ### Torque and moment

Homework Statement Attached image Homework Equations The Attempt at a Solution The book says that the force P causes a torque about the x axis. Why is it not a moment about x? Why is it specifically a torque in this case?
9. ### Shear stress in thin wall beams

Homework Statement http://postimg.org/image/9va37id55/ The question is to find the shear stress at the points A, B and C. The solution uses the sectioning planes aa, bb and cc to do so. For example, at C, how should I know whether to use a horizontal or vertical sectioning plane. Also, how...
10. ### Dew point temperature

Homework Statement This is a diagram T-v diagram for a closed system consisting of a sample of moist air that is cooled at constant pressure can someone explain what happens for the state of the water vapor to move from d to 2? if its cooling at constant pressure, why does it not stay on the...
11. ### Dimensional analysis

Homework Statement How do I set up a matrix to find the combination of ( M(L^2)/T ) and I ( L^4) that results in units of M/ ( L^2 T^2 ) ? Homework Equations The Attempt at a Solution I think it looks something like [ 1 0 2 4 -2 0 ] * [ a1, a2, a3] = [1 -2 -2] but the dimensions of...
12. ### Pressure force on a control volume

Homework Statement http://postimg.org/image/4a8sv6umh/ Why do the pressure forces due to p1 and p2 act in the same direction? Homework Equations The Attempt at a Solution I thought that, given the direction of the flow, the pressure force on the bottom and top would act in opposite directions
13. ### Momentum relation for control volume

Homework Statement http://postimg.org/image/i4p19540z/ Homework Equations Resultant force on the control volume = Mass flow rate (Velocity outlets -Velocity inlets) The Attempt at a Solution I am just wondering if the 4cm is called depth, then what is the term for the "into the paper"...
14. ### Dew point and exhaust temperature

Homework Statement I'm trying to find some information on "How does the dew point control the exhaust temperature of a thermodynamic cycle?" Homework Equations "The dew point is the temperature at which the water vapor in a sample of air at constant barometric pressure condenses into liquid...
15. ### Dimension Analysis and buckingham pi

Homework Statement can someone explain why we are interested in forming dimensionless products and why only n-j of them should be formed from the problem's variables? Homework Equations Step 1: List the variables in the problem Step 2: Express each of the variables in terms of basic...
16. ### System of linear equations

Homework Statement I'm given a system of equations and I'm told to: Solve this system by hand in 4-decimal digit arithmetic with rounding, using Gaussian elimination without pivoting and backward substitution Homework Equations The Attempt at a Solution When they say 'without backward...
17. ### Hydro static forces on curved surfaces

Homework Statement http://postimg.org/image/4fhu5k9r9/ [Broken] Can someone explain what is meant by 'missing water' in this solution diagram The original question diagram had no such water above the gate AB Homework Equations The Attempt at a Solution
18. ### Representing distributed loads with singularity functions

Homework Statement could someone explain why the terms in red represent the red distributed load in the attached diagram? Homework Equations http://postimg.org/image/3x0wywr4v/ [Broken] The Attempt at a Solution the only term I think I understand is the -3<x-0>^0 but I'm not sure of the rest
19. ### Plotting singularity functions

Homework Statement Can someone explain how the expression for V(x) is plotted? Homework Equations The Attempt at a Solution I understand the plots for the dotted lines but not how they got the actual plot for V(x)
20. ### Inner product for work

Homework Statement http://postimg.org/image/lgphyvggz/ Homework Equations The Attempt at a Solution can someone explain where that transpose came from in (3.3)?
21. ### Only conservative vector fields are path independent?

does anyone have a proof of this?
22. ### Gradient vector perpendicular to level curves?

Homework Statement can anyone explain/prove why the gradient vector is perpendicular to level curves? Homework Equations The Attempt at a Solution
23. ### Probability distribution question

Homework Statement http://postimg.org/image/bleosmrep/ Homework Equations The Attempt at a Solution can someone explain the last line of the solution; where did 1 - 6.25/10^2 come from? Homework Statement Homework Equations The Attempt at a Solution
24. ### Question on work

Homework Statement "An insulated box is initially divided by a frictionless, thermally conducting piston. One side of the piston is 1.5(m^3) of air at 400k, 4bar. The other side is 1.5(m^3) of air at 400K,2 bar The piston is released and equilibrium is attained, with the piston experiencing...
25. ### Two small circuit questions

Homework Statement http://postimg.org/image/dd3s2edih/ [Broken] Is it possible to simplify the first circuit? And for the second circuit, does every other component in the circuit have 6A? Homework Equations The Attempt at a Solution
26. ### Voltage of capacitor

Homework Statement http://postimg.org/image/4m0huqxpj/ Homework Equations v(t)=v(infinity)+ [v(0) - v(infinity)]^e(-t/RC) The Attempt at a Solution I found Vo(0) to be 8V, but I'm not sure about about v(infinity) and R If the switch is at B and the capacitor is an open circuit at steady...
27. ### Two questions on retrieving thermodynamic properties

Homework Statement ''A rigid insulated container fitted with a paddle wheel contains 5lb of water, initially at 260F and a quality of 60%. The water is stirred until the temperature is 350F. For the water, determine the work.'' How do we know whether the state of the water at 350F is...
28. ### Angular momentum question

Homework Statement http://postimg.org/image/qghh7y1vr/ [Broken] can someone explain why angular momentum is conserved about O? Homework Equations M(P) = d/dt (h(P)) + v(P) x mv(G) h(P) = I(G)w + r(G/P) x mv(G) The Attempt at a Solution edit: nvm, I got it
29. ### Hypothesis test

Homework Statement "Is there sufficient evidence to support the claim that the mean content of all such containers is at least 3 litres? Homework Equations The Attempt at a Solution I'm not sure what H0 and H1 will be H0: The mean content is not at least 3L H1: The...
30. ### Simple probability question

Homework Statement My book says that P(C∩G) = P(G)P(C|G) but shouldn't it be P(C∩G)= P(C)P(C|G) ? Homework Equations The Attempt at a Solution