Calculate the strain on the rope. A 10 meter long rope is streched 3.0 cm when a man hangs on it's end.
One way to calculate strain is: (change in length) / (initial length)
3.0 cm / 10 m = 3.0 cm / 1000 cm = 3/1000 = 0.003
Thanks Geno, I thought strain would have some kind of unit attached to it
Is that a normal way to do it?
Hi Melody, Geno is right, Strain is a dimensionless ratio (you might be thinking of Stress which has dimensions of force per unit area).
Thanks Alan, I wasn't thinking of anything. I know very little physics :)
So strain does not have anything to do with breaking point then?
I mean elastic can double in length without breaking but most things break much more quickly :/
By definition, strain is just change in length divided by original length. The size of the strain will depend on the applied stress, and if the stress is too great the material will break. Elastic materials can get to larger strains than, say, ceramics, before breaking.