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A wheel with 10 metallic spokes each 0.5...

A wheel with 10 metallic spokes each 0.5m long is rotated with a speed of 120 revolutions/min in a plane normal to the horizontal component of the earth's magnetic field `H_(E)` at a place if `H_(E)=0.4` G at the place, what is the induced emf between the `axxk` and the rim of the wheel ? Take, 1 gauss `(G)=10^(-4)T.`

Text Solution

Verified by Experts

Given :
Induced emf, `e=Blv(or)e=(1)/(2)Bl^(2)omega["where,"v=romega,l-2R]`
Also, `omega=2pif=2pixx(120)/(60)`
`omega=4pi`
Solution :
emf,`e=(1)/(2)xx4pixx0.4xx10^(-4)(0.5)^(2)`
`=6.28xx10^(-5)V` The number of spokes is immaterial be cause the emf's a cross the spokes are in parallel.
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