Could someone please help me on this question please. It's from m1 jan 2004 (question 4). Thank you:

Two small rings, A and B, each of mass 2m, are threaded on a rough horizontal pole. The coefficient of friction between each ring and the pole is . The rings are attached to the ends of a light inextensible string. A smooth ring C, of mass 3m, is threaded on the string and hangs in equilibrium below the pole. The rings A and B are in limiting equilibrium on the pole, with
BAC = ABC = , where tan  = , as shown in the diagram above.
(a) Show that the tension in the string is mg.
(3)
(b)

Question

Could someone please help me on this question please. It's from m1 jan 2004 (question 4). Thank you:

Two small rings, A and B, each of mass 2m, are threaded on a rough horizontal pole. The coefficient of friction between each ring and the pole is . The rings are attached to the ends of a light inextensible string. A smooth ring C, of mass 3m, is threaded on the string and hangs in equilibrium below the pole. The rings A and B are in limiting equilibrium on the pole, with 
BAC = ABC = , where tan  =  , as shown in the diagram above.
(a)	Show that the tension in the string is  mg.
(3)
(b)

anonymous · Answer

Btw after the word is it's "mu"

anonymous · Answer

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