Shown a square loop of side 5 cm beign moved towards right at a constant speed of 1 cm/s. the front edge enters the 20 cm wide magnetic field at ` t=0`. Find the emf induced in the loop at `(a)t =2s, (b) t =10s, (c ) t= 22s, (d)t =30s`.

Explanation

Here` u=1 cm//s, B=0.6T`
`(a) At t=2 sec,`
`Distance moved =2xx1 cm//s=2 cm`
`e=(d phi)/(dt)`
`=(0.6xx(2xx5xx-0)xx10^(-4))/2`
`=3xx10^(-4) V.`
`(b) At t=10 sec,`
`The flux linked does not change with time`
`:. e=0.`
` (c )At t=22 sec.`
`Distance moved =22xx1= 22 cm.`
`The loop is moving out of the field ad 2 cm outside,`
`e=(d phi)/(dt)=Bxx(dA)/(dt)`
`=(0.6xx(2xx5xx10^(-4))/(2)`
`=3xx10^(-4) V.`
`(d) At t= 30 sec.`
`The loop is totally outside and flux linked `
`=0`
`:. e=0.`