Recent content by app

  1. A

    First Area Moment and Centroidal Co-ordinates

    I'm sorry,but that is what i'm not being able to do.could u please explain it?The appropraite limits of integration will be from 0 to r,where r is radius of quarter circle.
  2. A

    First Area Moment and Centroidal Co-ordinates

    1.Homework Statement There is a quarter circle.The centre of the circle of which the quarter circle is a part,is at the origin (0,0).Find the centroidal co-ordinates for the quarter circle.The equation of the circle for which the quarter circle is a part,is x2 +y2 = R2. where R is radius...
  3. A

    Newton's Laws Of Motion

    I cant do anythng abt that, thats our exam rules here, its tough competition. And ya, ofcourse, some others out of that 75 are simpler. But if one can do this problem in the least possible time,(i dont mean 1 minute for this problem), then he can save time for the other problems. And it is not...
  4. A

    Newton's Laws Of Motion

    The problem does not state that the two blocks, B and C move together (i.e. that they have the same acceleration). It was just a hint given at the back of the book. So, u say that there is no direct method to identify which blocks will move together, or whether they all wud move with different...
  5. A

    What am I missing?

    Then i dont think it'll ever come to 15. maybe the answer in the book is wrong or there is a misprint in the question. I didnt notice that it was the weight of the box that is 200. I thought it was the mass. if u take it to have a mass of 200 kg and not weight, then the answer is 15m. Other...
  6. A

    What am I missing?

    Ya, obviously the answer will be 15m. And where did the g go? its 4000 J, not 400. Now 76% of the total work done by you will be 4000. Now, solve that. In PF, u'll have to do some work by yourself, no one will post full solutions (PF rules).
  7. A

    What am I missing?

    I just get the feeling that the 2 m is the vertical height above the ground to which the box is lifted. So, you can surely find the potential energy of the box at a height of 2m, right? Where does that P.E. come from? Now 24% work is wasted. leave that. So, the rest 76% of your work is spent in...
  8. A

    Newton's Laws Of Motion

    Oh, ok. I got it. But what about the blocks B and C moving together? why will they move together? I mean why will B and C have the same acceleration? but i all the frictional forces will not act towards left. the frictional force on B due to A and on top of C due to B, will be directed towards...
  9. A

    Newton's Laws Of Motion

    INTRODUCTION: The following is a problem of "Newton's Laws Of Motion". It is a typical problem of this chapter. I am having problems with some parts. THE PROBLEM IN BLACK AND WHITE: "Find the acceleration a_{A}, a_{B} and a_{C} of the three blocks shown in the diagram (not included here)...
  10. A

    Relative Velocity concept help

    WHY 0 m/s? why have u added 0m/s north in each of earth's ref. frame and rain's ref. frame?
  11. A

    Relative Velocity concept help

    Thanks, I feel i am starting to understand, but could u please tell me why it is v_{rel} = v_{man} - v_{rain} and not v_{rel} = v_{man} + v_{rain} or why not v_{rel} = v_{rain} - v_{man} ? Thanks a lot (Thats all i can give u).But of course i will always remember you as the "GREAT MAN WHO...
  12. A

    Relative Velocity concept help

    i dont think one can do all rel. vel. problems with that... Thanks a lot. But now, what if the rain is not vertical, that is no component is zero. Lets say: "To a man moving due north with a speed 5m/s, the rain appears to fall vertically. When the man doubles his speed, the rain appears to...
  13. A

    Relative Velocity concept help

    I guess this is going to be my worst thread. I'm so sick of this stupid concept "relative velocity" that i'm in no mood to present this thread in my "exemplary style" for which i have been included in the "best homework threads" section. I'm sorry for that, but its true. I have no problems...
  14. A

    A few problems on MOTION IN ONE DIMENSION

    Thanks... THANK YOU: Hey, thanks a lot for helping. Now I got the second one. But are you sure the book's answer for the first one is wrong? I am quite sure it is wrong. But was just being surer. Anyway, thanks again.
  15. A

    A few problems on MOTION IN ONE DIMENSION

    I Dont Get The Second Answer. I think the first one is ok, i.e. maybe the answer given in the book is wrong. But i dont get your second answer. and its 155 km/h and not m/s. its a jeep, not a supersonic jet. only the velocity of bullet is 180m/s.
Top