Recent content by Matthias85

Thank you for your help. May you please share your calculations with me?

The AL cylinder is placed on a steel plate in furnace with fan turned on to ensure uniform heat distribution. I followed your advice and taken into account decrease in Br and Gr numbers. Time has now reduced to 7 and a half hours.

I can't find my precious calculations. I attach my most recent calculations, which still seem to be wrong. I am pretty sure it should not take longer than half an hour to heat up a small AL cylinder to ~100 deg C.

As stated in the first post: A solid cylinder made out of AL 6061-T5, dimensions d 10mm, L 28mm. Is put into an oven pre-heated to 100 deg C. How long will it take for the cylinder to reach 100 deg C ?

Homework Statement A cylinder made out of AL 6061-T5, dimensions d 10mm, L 28mm. Is put into an oven pre-heated to 100 deg C. How long will it take for the cylinder to reach 100 deg C ? Homework Equations None given, this is not a homework question or even material I have been taught. I have...

I see, distance L for each spring is given in question, is it k2 (L/4)θ+x and k1(L/2)θ ? In which case the differential equation of motion become (now with correct signs) Iθ + k2 (L/4)θ+x - k1(L/2)θ =0 mx - k2 (L/4)θ+x =0

I am struggling with the following question, it is a mixed (lever and linear) 2DOF vibration problem, something I never came across before. I am afraid I am missing something on the FBD, thus the differential equations of motions are wrong. Homework Statement Homework Equations...

Thanks for quick reply. I am not using any method as I have no idea how to workout limits. Previous question gave me limits, this says that x-axis and y-axis are in the 1st quadrant instead.

Homework Statement The question asks me to find the coordinates of the centroid of a uniform lamina enclosed by curve y=1-x^2. X axis and Y axis are in the 1st quadrant. Can you please tell me how to work out the limit for this equation?

This question is now solved, the answer must have been miss-typed. Thank you guys for help. PetrerO, I think you are right about value of gravity as I just did very similar question to this one, and got correct answer when I used g at 10m/s/s.

Answer says 36.2kW however the sheet also says that some of the answer may be mis-typed :) Yes, the question is asking for the minimum power of the engine. Do you know if there's a way of solving it without knowing mass of the car?

Thanks that helps ! I am still getting 36.4W not 36.2W :( KE = 0.5x600x22^2 = 145200J PE= 600x9.81x100Sin(18.43) = 186131J WD = 331331J Power = 331331/9.09 = 36450W

h=100Cos(18.43)=94.87m g=9.8m/s/s Could you please solve this question for me, so I know where I am making the mistake?

I've tried that I got incorrect answer of 70k W, should be 36.2W Maybe the 600kg I've quoted from section B is misleading. Can this question be solved without knowing the mass of the car?

So what's the next step? I have tried using 1/2mv^2 + mgh but I kept getting wrong answer. Maybe the 600kg is incorrect, can this question be solved without knowing weight of the car?