Question

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The systems shown below are in equilibrium. If the spring scales are calibrated in newtons, what do they read? Ignore the masses of the pulleys and strings and assume the pulleys and the incline are frictionless. (Let m = 5.09 kg and θ = 28.0°.)
scale in (a) - ???
scale in (b) - ???
scale in (c) - ???
scale in (d) - ???

Answer 1

m g = 5.09 * 9.81 = 49.9 N

a) 49.9 = tension in string = what scale measures
b) 49.9 same reason
c) now 99.9 two strings with previous T so twice the force
d) 49.9 * sin 28 = 23.4