# 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
7 years, 1 month ago

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90 degrees

- 7 years ago

cn u pls post the ans ? is it 45

- 7 years ago

Largest possible fraction should be 1/2

- 6 years, 12 months ago

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

- 6 years, 11 months ago

22.5

- 6 years, 11 months ago

- 6 years, 5 months ago

What is the source of this question...?

- 4 years, 3 months ago

Its from harvard university's website

- 3 years, 6 months ago

22.5

- 3 years, 7 months ago

45

- 7 years ago