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A drat races a 3 sided coin rematch!?
A solid spherical drat of mass m radius r where g'=0.5g
races a solid "3 sided coin" of mass m radius r and of length
equal to 4r where g'=3g start rolling down the same incline at the
same time.
And the winner is?
Fifi:
Suggested categories: hobbies & craft
Ans: no,no,no,no
1 個解答
- KoshkaLv 51 十年前最愛解答
Can the 3 sided coin be a cylinder?
Are they on different planets?
Does the lenght of the cylinder matter?
See, I am not as smart as my contacts =/
Why g? Do we need to find KE?
KE of rotating sphere=1/2 * (2/5*m*r^2) *(v/r)^2
KE of rotating cylinder 1/2 (1/2 m*r^2) *(v/r)^2
________________________________________
Edit:
OK, Hmmm, in haste made mistake!
ke=1/2mv^2+1/2iw^2
Sphere: 1/2 m * (sqrt 10*0.5g * h)/7 + 1/2 (2/5 mr^2) *((sqrt 10*0.5g * h)/7)r^2
I do not like to make up excuses, so I shall leave it to more knowledged people like mathematicians, physicists and engineers to take it feom there.
Good luck with that 3 sided coins folks!
Snow is waiting! Yipee!!!
資料來源： Obnoxious!
