What is meant by.
Strength to weight ratio = (strength)/(weight).
A ratio of >1 is usually a good thing. That means that the thing in question has more 'strength' than weight/mass.
Pretty cut and dry.
its a measure of the efficiency of a structure - normally associated with things like bridges.
It compares the weight of the structure itself to the amount of weight it can carry/support without collapsing.
For example the miniature wood-stick bridges you build at school will have a very high strength to weight ratio - in the hundreds, sometimes the thousands. This is because they weigh only a couple dozen grams, yet are able in some instances to hold one or two hundred kilograms without breaking!
A modern-day metal bridge however will have a strength to weight ratio nearer to 1.
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