A bar magnet of magnetic moment 6 J/T is aligned at 60° with a uniform external magnetic field of 0.44 T. Calculate
(a) the work done in turning the magnet to align its magnetic moment
(i) normal to the magnetic field.
(ii) opposite to the magnetic field, and
(b) the torque on the magnet in the final orientation in case (ii).
(a) (i)
M = 6 J/T
Q1 = 60º Q2 = 90º
B = 0.44T
W = MB(cosQ1 - cosQ2)
= 6 x 0.44(cos60º - cos90º)
= 6 x 0.44 x ½
= 1.32 J
(a) (ii)
Q1 = 60º Q2 = 180º (opposite to magnetic field)
W = MB(cosQ1 - cosQ2)
= 6 x 0.44(cos60º - cos90º)
= 6 x 0.44 x (½ - (-1))
= 6 x 0.44 x 3/2
= 3.96 J
(b) = M X B
= MB sin Ø
= 6 x 0.44 x sin 180º
= 6 x 0.44 x 0
= 0
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(a) Estimate the number of electrons transferred (from which to which?)
(b) Is there a transfer of mass from wool to polythene?
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, approximately.
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(c) Determine the equivalent resistance of networks shown in Figure
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(a) Estimate the number of electrons transferred (from which to which?)
(b) Is there a transfer of mass from wool to polythene?
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(c) Surface waves.
(d) Space waves.