- #1

NTesla

- 175

- 22

- Homework Statement
- Kindly see the attached pic for the Question. I'm solving part b of the question.

- Relevant Equations
- F = ma

This question is from the book Kleppner and Kolenkow Q 3.8:

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My attempt is posted here:

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The value of a(minimum) that I'm getting is different from the official solution. The official solution is posted here:

___________________________________

Here's 2 problems that I'm encountering:

(a) The value of a(minimum) that I'm getting is different from the official answer. If my calculations are wrong, I'm not able to find out where am I going wrong. Kindly help.

(b) From the equation of N(in my calculation), if theta tends to zero, then N tends to mg. This makes sense to me.

However, in the official answer(posted above), if we try to see what happens to value of N as theta tends to zero, then N becomes mg/mu(the symbol of coefficient of friction). This doesn't make sense to me. So, which equation of N is correct ?

___________________________________

I understand that in the official answer, the equations have been written from inertial frame of reference. I understand those equations and they are right according to me. This is causing a conundrum, that if I'm finding the official equations right(which I do), then the value of a(minimum) must be right as given in the official answer. But I'm also not able to find where my equations are wrong(if they are wrong), leading to different value of a(minimum).

___________________________________

My attempt is posted here:

___________________________________

The value of a(minimum) that I'm getting is different from the official solution. The official solution is posted here:

___________________________________

Here's 2 problems that I'm encountering:

(a) The value of a(minimum) that I'm getting is different from the official answer. If my calculations are wrong, I'm not able to find out where am I going wrong. Kindly help.

(b) From the equation of N(in my calculation), if theta tends to zero, then N tends to mg. This makes sense to me.

However, in the official answer(posted above), if we try to see what happens to value of N as theta tends to zero, then N becomes mg/mu(the symbol of coefficient of friction). This doesn't make sense to me. So, which equation of N is correct ?

___________________________________

I understand that in the official answer, the equations have been written from inertial frame of reference. I understand those equations and they are right according to me. This is causing a conundrum, that if I'm finding the official equations right(which I do), then the value of a(minimum) must be right as given in the official answer. But I'm also not able to find where my equations are wrong(if they are wrong), leading to different value of a(minimum).