As shown in the figure, a magnetic is moved with a a fast speed towards a coil at rest. Due to this, induced electromotive force, induced charge in the coil are `E`, `I` and `Q` respectively. If the speed of magnetic is doubled, the incorrect statement is

Options

A. E increases
B. l increases
C. Q remains same
D. Q decreases

Answer

D

Explanation

Induced emf E=IR
or `I=(E)/(R)`
and `E=(d phi)/(dt)`
`I=(dphi)/(dt" "R)`
induced charge q=I.dt
`=(d phi)/(R)`
If speed is doubled. Then dt decrease. Hence, E, I increases, but q will not increase.