Homework Statement
[/B]
Homework Equations
a⋅(b x a) = 0
The Attempt at a Solution
Is my working below correct? In particular, can you apply the rCB to both the first part of the bracket (0.2j) and the second part (w x rCB) individually like that?
My second question relates to:
Is...
Homework Statement
Homework Equations
ml2/12
The Attempt at a Solution
So according to my databook:
The axis x'-x' in the question corresponds to axis ZZ in the databook image above. That means in terms of radius, the moment of inertia about axis x'-x' is mr2/2. So in light of this...
Homework Statement
Homework Equations
RAO = b(Sinβj+Cosβk)
The Attempt at a Solution
[/B]
The box in red is ω. However I am unsure of where they got the box in blue from? As mentioned above, RAO = b(Sinβj+Cosβk) so not sure where they got the box in blue from? I know of the vector triple...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
I know that they got a rank of 2 since there are 2 linearly independent columns but what if we decided to count rows? In that case we would have 4 linearly independent rows which would suggest the rank is 4? How do we...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
The left hand side (red box) is the data sheet provided to us in the exam. The right hand side (blue box) is Wolfram Alpha. The data sheet says that the inverse Laplace transform of 1/s is equal to u(t) (i.e. the unit step)...
Homework Statement
Homework Equations
The Attempt at a Solution
I have done question 1.18 and I understand it completely. However, for question 2.5, I do not understand how they got G(s)? Why isn't the G(s) in question 2.5 the same as G(s) at the bottom of question 1.18? I asked my lecturer...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
I understand how they got the answer and the calculations they did but I have 3 questions about this screenshot.
1) Why the box in red is the transfer function? Is there a way to tell this from the Y(s) = ... expression?
2)...
Homework Statement
[/B]
Homework Equations
N/A
The Attempt at a Solution
What I am confused about is where they got the (1/4)mR^2 + (1/12)ml^2 and (1/2)mR^2 from? I am guessing that these came from the integral of y'^2 + z'^2 and x'^2 +y'^2 but I don't understand how this happened exactly...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
I am confused as to where the ω3sin(θ)k term disappeared to? It is not included in the very last line? I asked my lecturer and he said it's ''constant'' but he kind of shrugged off the question. I understand everything...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
I have 2 (basic) questions about this system:
1) The question says that ωAB = ωABk, I understand that bold indicates vectors whilst the plain text indicates a magnitude so ωAB (magnitude) multiplied by k (direction vector)...
Homework Statement
http://photouploads.com/images/8ba21e.png
{moderator's not: Inserted image so it's visible without having to follow a link}
2. Homework Equations
a·(b x c) = b·(c x a)
The Attempt at a Solution
How did they get from the (b) to (c)? In particular, I am referring to the...
Homework Statement
Homework Equations
Torque = Force x Distance
Shear stress = Force/Area
3. The Attempt at a Solution
I know how to do this question as I've seen the mark scheme. However, initially I did it wrong. What I did was as follows:
Torque = Force x Distance
therefore...
Homework Statement
How do we obtain:
w = q - Δh
Homework Equations
The Attempt at a Solution
If you neglect the second half of the SFEE and simplify we get:
What is the next step from the last line in the above image to
w = q - Δh
I mean dw/dt = dq/dt - Δh
so if we multiply by dt we...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
I am confused what 5-5b and 5b-6 represent in the above TS diagram. I know that 1-2 is compression, 2-3 is cooling, 3-4 is compression and 4-5 is regeneration (since these are indicated in the block diagram) but as for 5-5b...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
My question is a simple one: how is the above equation for COPref different to the COPref equations I've already encountered (such as COPref = Qc/Win = (h1-h4)/(h2-h1). Is the above just a different form of these? Or is the...
Homework Statement
http://photouploads.com/images/ae1d2f.png
Homework Equations
N/A
The Attempt at a Solution
In the image linked above, I have copied and pasted 4 different slides. In the last slide, I am confused how they got the expression for T2 (the working out). I know that they did...
Homework Statement
Homework Equations
N/A
The Attempt at a Solution
I am trying to understand the above ph diagram (for a vapour compression cycle), In some examples, point 1 is situated as above in the image (i.e. to the right of the saturated vapour line) and at other times it's situated...
Homework Statement
2. Homework Equations
q = w+Δh
The Attempt at a Solution
I fail to understand how they obtained the 3 equations at the bottom. For the first one I understand that q = Δh since w = 0 but why is it h1-h4 rather than the other way around? Also, why does this h1-h4 equal...
So it has been quite a few years since I learnt about implicit differentiation so the content is a bit rusty in my mind.
x=rcos(θ)
How do you find dx/dt?
I know the answer but I am trying to figure out why. I mean dx/dt can be written as (dx/dθ)*(dθ/dt) so why is the answer not just...
Hello,
I am kind of new to Matlab so the questions I will ask probably sound a bit basic. Anyways, here goes:
I want to create the matrix below which has both constants and variables. How can I do this? I know how to create a normal matrix (e.g. B = [1 0 2; 3 4 5; 0 2 3]) but I don't know how...
Can someone explain why the slope dy/dx = 0 at x = L/2? L/2 is the midpoint and there would be a deflection here so surely the slope of the deflection curve shouldn't be 0? I'm finding it hard to visualise this.
EDIT: I think I understand the above. The slope of the deflection curve at x = L/2...
The circumference of the shaded ring is 2πρ however I am struggling to understand how the area, dA, of the ring is equal to (2πρ)dρ? I mean the circumference varies depending on the value of ρ so surely we can't multiply by dρ to yield the entire area of the shaded ring? If we decided to go by...
Homework Statement
Homework Equations
M = 3(L – 1) – 2J
L= number of links, J = number of joints
The Attempt at a Solution
As far as I can see, using the above L and J values for each linkage yields the correct M value. However, the L and J values lead me to think I'm missing something...
The above states that the velocity of point Q relative to P is represented by dr/dt. However, it also states that ∂r/∂t is the apparent velocity of Q in Pxyz. How does that make sense? I mean P is the origin of axes Pxyz so surely the velocity of point Q relative to P should be the same as the...
I have several questions that I am seeking clarification on. The first 2 are rather simple:
1) The formula for r describes the blue streamline (the stagnation streamline) right? (Just confirming)
2) I assume that the stagnation streamline is called so because it passes through the stagnation...
The working out states that v = (m/r)sin(theta) but surely this should be (-m/r)sin(theta) ? I mean there is a negative in front of the ∂Ψ/dx ?
Also, if v=0 then 0 = (m/r)sin(theta), therefore sin(theta) = 0? And from this we know cos(theta) = 1 or -1 which would mean u = Uinfinity + (m/r) or...
I know that the circulation is defined as the counter clock wise integral around the closed curve of the flow velocity component along the curve but what is its meaning in real life? I mean what does circulation actually refer to in real life? Also could someone explain the above image? What is...
How did they go from ∂Ψ/dθ = m to Ψ = mθ + f1(r) ?
I mean I understand how they got mθ but can someone explain the f1(r) term?
Similarly, how did they go from -∂Ψ/dr = 0 to Ψ = c1 + g1(θ) ?
I understand how they got c1 but why the additional term?
I can't provide further working out as...
Ok I know this is simple resolving but I'm a bit confused. If we resolve forces in the vertical y direction (as in the attached image), we obtain Rcos(theta)-W=0 and hence Rcos(theta) = W meaning R = W/cos(theta) [where theta = 18 degrees]
However, if we resolve forces along the direction of...
Can anyone explain why sum of Ft has been set to be = 0? The slope is smooth so no frictional forces act but by setting it to 0 they are neglecting the component of the weight along the slope? Having said that, this is a curved slope and not a straight one so does the component of the weight...