Question

3. Why sine bar is not suitable for measuring angle above 45 degrees?

Answer 1

The graph for dϴ vs. ϴ is similar to that of exponential curve which steeps at around 45°. Hence it is not preferred to use sine bar for measuring angles greater than 45°. ... Sine bar can not be more than 45 degree, because it need to have proper vertical support this is hard for above 45 degrees.

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