Question

Why potential energy is taken as negative?☺?

Answer 1

We say that ,
an object that is an infinite distance away from the Earth has zero gravitational potential energy , with respect to the Earth.

Because a negative amount of work is done to bring an object closer to the Earth, gravitational potential energy is always a negative number when using this reference point.

Answer 2

Potential difference is indeed a difference. So, what happens if you subtract 0 from 5 i.e. 5–0 = +5 . Now, if you do 0–5, what do you get? You get -5. Thus, it depends how measurements are being taken. It is based on which terminal is taken as ground. If the ground is at higher potential then of course you will get a negative potential difference....

HOPE IT HELPS you....

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