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File: WeighingTheOptions A ChallengeQuestion ... !! WeighingTheOptions [[[< images/ScalePicture.gif ]]] Consider a good, old-fashioned spring-balance. The more you hang from it, the larger the reading. Suppose it's been calibrated, and when you hang one kilogram from it the dial reads 1kg. [[[> images/ScaleQuestion.gif ]]] Now look at the arrangement we have here on the right. We have two frictionless pulleys and a light, inextensible string such as is only ever found in a physics textbook. We put the (effectively massless) spring balance in the middle, and we hang a kilogram from each end of the string. What reading do we get?