# Exercise 2.25 Rope between inclines

A rope rests on two platforms that are both inclined at an angle $\theta$ (which you are free to pick), as shown in Figure above. The rope has uniform mass density, and the coefficient of friction between it and the platforms is 1. The system has left-right symmetry.

What is the largest possible fraction of the rope that does not touch the platforms?

What angle $\theta$ allows this maximum fraction?

Note by Beakal Tiliksew
6 years, 5 months ago

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## Comments

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90 degrees

- 6 years, 3 months ago

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cn u pls post the ans ? is it 45

- 6 years, 3 months ago

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Largest possible fraction should be 1/2

- 6 years, 3 months ago

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answer is fraction:- 3 - 2^1.5 and angle is pi/8 i.e. 45/2 in degrees

- 6 years, 3 months ago

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22.5

- 6 years, 2 months ago

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You may see the full solution here: https://www.physics.harvard.edu/uploads/files/undergrad/probweek/sol89.pdf

- 5 years, 9 months ago

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What is the source of this question...?

- 3 years, 7 months ago

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Its from harvard university's website

- 2 years, 10 months ago

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22.5

- 2 years, 11 months ago

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45

- 6 years, 4 months ago

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