Recent content by dreamliner

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    How Does Channel Slope Affect Water Depth?

    We just touched on the subject before end of class today, so I'm not sure if this is correct, but using the formula for hydraulic radius R=A/P - where P is the wetted perimeter: R= A/P can be re-written as (w*y)/(y+y+w)= (w*y)/(2y+w) giving P=2y+3. Looking at it I'm not sure if this will work...
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    How Does Channel Slope Affect Water Depth?

    Homework Statement A rectangular channel has a width of 2 meters, and an slope of 1:80. The Manning's number for the entire channel is n = 0,014. In this situation the depth is y= 1,50m. The flow of water is normal. Further down the slope decreases to 1:150 and the width increases to b=3...
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    Expression for pressure in a brake system - is this correct?

    So this part is correct? I might be about to break some major rules of physics here, but I'm pretty much guessing now... Would the force on the piston be the amount about the pivot* distance b?
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    Expression for pressure in a brake system - is this correct?

    Indeed. I suspect it's a case of hurrying. "Pascal's law uses F/A. I already have a F in the assignment. Great!". Would it be correct to use F = P*A where P would be the applied force and A would be the surface area of the pistons, and then multiply the results with the distances?
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    Expression for pressure in a brake system - is this correct?

    Well, working on the assumption that moment force is force *length of the arm the force is working on, the amount about the pivot would be the applied force F*the distance a and the moment at the piston would be F*the distance b. The relation being that the force F is the same in both cases...
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    Expression for pressure in a brake system - is this correct?

    Homework Statement Write an expression for the force applied to the brake caliper in the braking system(hydraulic) of a bicycle. F= force applied to the brake lever a = distance between F and the pivot point of the brake lever. b= distance between pivot point and lever piston. d1= diameter of...
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    Solving Truss Problems: Finding Unknown Forces | Learn Mechanics

    Hm. I will certainly give it a go. Thank you. Another question when it comes to trusses(I only started learning about them on Friday, so my knowledge is very limited.) In the figure both A and B are fixed nodes but are they also considered to be joints in the truss?
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    Solving Truss Problems: Finding Unknown Forces | Learn Mechanics

    Thank you for replying so quickly. Unfortunately I suck when it comes to vectors, but I suppose you mean constructing a triangle of forces? If so it would have to consist of rods AC and BC, as well as force F. All forces meet in joint C so equilibrium would be present. But in order to...
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    Solving Truss Problems: Finding Unknown Forces | Learn Mechanics

    Homework Statement You are given truss ABC. In joint C there is a horisontal force F(13,2kN). a is the measurement between A and B, and b is the measurement between A and C. Calculate forces Nac and Nbc. Homework Equations ƩMa=0 ƩFy=0 ƩFx=0 The Attempt at a Solution My main...
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    Calculate forces on a fixed beam

    So in this case it should be only q*4,1(the length of the beam force q is working on) even though force q isn't distributed across the entire beam? (I was under the assuption you had to consider cg of force q in such cases) Should have been a moment arm distance there, yes. So the correct...
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    Drawing a shear force diagram with loads working at an angle

    I was wondering how you incorporate an angled load into a shear force diagram? So far I've only been working with vertical loads and I've looked through my entire book without finding an example with loads at an angle, so I'm not sure what to do here. I know I have to end up at 0 so I see I...
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    Calculate forces on a fixed beam

    Homework Statement A beam ABC is fixed in point A. There is an evenly distributed load q working on top of the beam. In addition there is a diagonal load F working at point C. Calculate force Ax, Ay and the reaction couple MA. The Attempt at a Solution Please see attached file...
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    Find forces acting on a combined beam with load.

    Yes I got a little impatient there. I tried to delete my first post and use this one instead since it was basically the same question, but no go there. Anyway. Looking at Beam ABC from my drawing. If you are supposed to use the length from cg of the load to A, would this be correct: q*4,3(the...
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    Find forces acting on a combined beam with load.

    I was wondering if someone could have a look at my calculations. I believe I'm on the right track but I keep getting wrong answers, but I might be mixing + and - somewhere. I'm also a little unsure about the right way to incorporate the force working on top of the beam. The task reads: A...
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