Solution

ID: past-exam-of-the-mathematical-methods-ii-course-of-the-university-of-oxford/2016-resit/11/a/solution

The three nearly horizontal segments have lengths . To first order in small transverse slopes, the upward force on the first point mass is . The force on the second is . Applying Newton's second law to masses therefore gives
The approximation treats the string as massless, retains the imposed equilibrium tension and neglects gravity, as stipulated.

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