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Electrons are emitted by a hot filament ...

Electrons are emitted by a hot filament and are accelerated by an electric field as shown in figure .The two stops at the left ensure that the electron beam has a uniform cross-section.

A

(a)The speed of the electron is more at B than at A.

B

(b)The electric current is from left to right.

C

(c )The magnitude of the current is larger at B than at A .

D

(d)The current density is more at B than at A.

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The correct Answer is:
A
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