Yahoo Answers: Answers and Comments for Plz help me to finish this physics question? [物理學]
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From alfred
zhHantHK
Sat, 08 Apr 2017 14:38:40 +0000
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Yahoo Answers: Answers and Comments for Plz help me to finish this physics question? [物理學]
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https://hk.answers.yahoo.com/question/index?qid=20170408143840AAeAl8i
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From 天同: (a) Given PQ = L, hence PR = L.cos(40), and RQ...
https://hk.answers.yahoo.com/question/index?qid=20170408143840AAeAl8i
https://hk.answers.yahoo.com/question/index?qid=20170408143840AAeAl8i
Sun, 09 Apr 2017 15:31:20 +0000
(a) Given PQ = L, hence PR = L.cos(40), and RQ = L.sin(40)
Area of loop = (1/2).(RQ).(PR) = (1/2).(L.sin(40)).(L.cos(40))
= [(L^2)sin(40)cos(40)]/2
Magnetic moment of current loop = current x area = [I.(L^2)sin(40)cos(40)]/2
The direction of magnetic moment is given by the RightHandGripRule, and is pointing into the paper, i.e. in the ve zdirection.
(b) Torque = [B.I.(L^2)sin(40)cos(40)]/2
The direction of torque is in the ve ydirection.