# Shouldn't 20N forwards be +20N not -20N. Correct me if I'm wrong because this is what the textbook question says ? Relevance

Don't overthink this one. It doesn't relate to vector mechanics

or Mathematics in general.

If the forward direction is arbitrarily minus, then the reverse

direction is positive by convention.

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• You can define your positive direction any way you want. If forwards is negative, then backwards is positive.

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• Do you think north should be up on a map? Because those two questions are equivalent.

Here's how you do vectors. 20 N in one direction is different from 20 N in the opposite direction so we make the distinction by choosing a positive direction.

A vector pointing in the positive direction is positive. A vector pointing in the opposite from positive (negative) direction is negative.

In your problem, "backwards" is chosen as the positive direction. Forwards is chosen as the negative direction.

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• Anonymous
3 months ago

+80 N , what else ??

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