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Document Title
Fundamentals of Stress and Vibration 2. Engineering Mechanics Chapter
[A Practical guide for aspiring Designers / Analysts]

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- - - - (2.12)

[Fig 2.7: a point mass negotiating a frictional curved track]

The frictional work done is given as:

Frictional work done = N ∗ μ ∗ ds arc length = mg cosθ ∗ μ ∗ ds

We know from [Fig 2.7] that, ds cos θ = dx

Therefore, the frictional work done is given by: mg ∗ μ ∗ dx

Integrating the frictional work done for the entire curve between the limits of ‘x’ (0 to L), we get:

L
Total friction work done = μmg dx = μmg L
0

QP No. SSC/Q4401, Version 1.0, NSQF Level 7, Compliant with Aero and Auto Industries, Page 13 age 13
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