A copper rod of length 2 m fixed at one end is rotating with an angular speed `300 rad s^-1` about an axis normal to the rod and passing thorugh its fixed end. The other end of the end. The other end of the rod is in contact with a circulr metallic ring. A constant magnetic field of 0.4 T parallel to the axis exists everywhere. calculate the e.m.f. developed between the centre and the ring.

Explanation

Length of copper rod = I =2 m
Angular velocity = `omega` =300 rad `s^(-1)`
Velocity of one end of rod `=v_(1)=0`
B=0.4 T
velocity of the other end of rod = `v_(2)=omega I`
Average volocity = v= `(v_(1)+v_(2))/(2)=(0 -: omega I)/(2)`
`v=(omega 1)/(2)`
Induced emf = e = B vI
`e=B((omega 1)/(2))1`
`e=(1)/(2)B omega 1^(2)`
`e=(1)/(2) xx 0.4 xx 300 xx (2)^(2)`
e= 240 volt