Some of you were confused abt. velocity constraints..so, for a few days, lets restrict ourselves to rigid body constraints..

for practice and initiation, lets solve the following problems:

Given the velocity of one body, find that of the other. (don't blame me if you find these trivial)..

31 comments:

  1. 1. vy = vcotA

    2. v(of mass m)= vsecA

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  2. so, after all i was right in giving these easy problems..

    messed up the tan's and sec's..

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  4. correct piyush..but you must get these right on the first attempt. no good on the second!

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  6. kya yaar..do minute pehle tak to thik tha??

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  7. I THINK PIYUSH NEW ANSWER IS CORRECT???I ALSO GET SAME

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  8. is my ans correct??(see the second post)

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  9. no and no..no-one has got it right.

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  10. hey people..this is pathetic! these problems are real elementry..

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  11. bhaiya "1.vcotA"

    ye kaise galat ho sakta hai

    ye question to rotation ke subjective solved me hai

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  12. lets end this:
    1)Vy=VCotA
    2)V(of mass m)=VCosA

    ankush, you second part was wrong..

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  13. okk..

    bhaiya plz tell my mistake

    let velocity of m be u,...and 2m velocity is given v

    x1+x2= constant ......(x1 is distance frm pulley to m,..x2 is length of rope from pulley to 2m)

    x1+x2 = constant

    - dx1/dt = dx2 / dt

    u= dx2/dt.....(i)

    now,v=d(x2cosA) /dt
    =>v=cosA dx2/dt

    from (i) => v = u cosA

    u= v sec A

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  14. while differentiating, you have assumed A to be unchanging with time..

    he he, use this:
    components of velocity of any 2 pts. on a tight string/rod along the dirn. of the string/rod must be equal..

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  16. got my mistake....plz check this soln

    from the above soln
    u= dx2/dt.....(i)
    v=d(x2cosA) /dt

    but we need dA /dt if cosA is not constant

    here's the 3rd eqn

    x2sinA =constant

    distance between pulleys never changes

    got dA/dt from this...used some trigo

    finally got u = vcosA

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  17. how can we solve the question given in physics workshop(mechanics-2) qus -61,62,63 with help of COR theorem

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  18. bhaiya 2nd question
    Vcos theta = 2 V(of m)
    so V of m = V cos theta upon 2

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  19. nahi second mein string ke along velocity equate karni hai add nahi karenge dusra component dusri sting ke along hai

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  20. PLEASE REPLY ANUJ SIR THE PROBLEM I ASKED.HERE IN YOUR PROBLEM YOUR ANSWER IS CORRECT...

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  21. bhaiya...some more of these....(a lil more difficult ones..) would be really helpful...!

    thnx a lot..!

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  22. hi amritpal..i have a solution for your problem...

    i have assumed a center of rotation for the rod, and the rest is fairly simple..

    plz. you never want to assume a center of rotation in such problems, and without that the solution is complex. are you not satisfied with the problems i give??

    plz. yaar, stick to what your teachers teach.

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  23. hi sambhav, thy will be done.

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  24. PLEASE ANUJ SIR WHAT IS THE TOTAL KINETIC ENERGY OF THE LADDER WHEN THE LADDER TOP MAKES AN ANGLE THETA WITH THE WALL.PLEASE GIVE DETAIL BHAIYA.

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  25. hi amritpal. the total KE is equal to the loss in PE.

    which is:
    mg(L/2)(1-CosA)..if you assume A to be angle made by the rod with the vertical.

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