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A conductor of length l and mass m can s...

A conductor of length `l` and mass `m` can slide without any friction along the two vertical conductors connected at the top through a capacitor. A uniform magnetic field `B` is set up `_|_` to the plane of paper. The acceleration of the conductor

A

is constant

B

Increases

C

decreases

D

cannot say

Text Solution

Verified by Experts

The correct Answer is:
A
Let `v` is the velocity of conductor at any time, then induced emf: `e = Blv` …………..(i)
charge on capacitor : `q=Ce=CBlv`
Current in circuit: `I = (dq)/(dt) = CBl(dv)/(dt)`
for conductor `mg-Ibl = (mdv)/(dt)`
`rArr mg-CB^(2)l^(2)(dv)/(dt) = (mdv)/(dt) rArr (dv)/(dt) = (mg)/(m + CB^(2)l^(2))`
This is the acceleration of conductor which is constant.
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Knowledge Check

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