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Why is that in proving the theorem

Why is that in proving the theorem

Why is that in proving the theorem

Why is that in proving the theorem of minimum potential energy the potential "V" taken negative.Let us say i am applying a load to a spring and as a result spring is deflecting downwards?

RE: Why is that in proving the theorem


It's just a sign convention. You can use any mathematically consistant system. Many structural engineers prefer to call downwards deflection "+ve" and the corresponding bending moment positive also. Mathematically however, a downwards load causing a downwards deflection is usually referred to as "-ve" in the conventional x-y coordinate system.

Text books use either convention, depending usually on the author's preference.

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