Charge placed in a cavity in a conductor

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When a charge is placed in a cavity within a conductor, the electric field inside the cavity will not be zero. This is because the charge acts as a source of the electric field, and there is no conductor shielding it from the cavity space. The conductor will redistribute charges on its inner and outer surfaces to cancel the electric field within the metal itself, but the cavity will still experience an electric field due to the charge present. If the cavity is spherical and concentric with the conductor, the electric field inside the cavity will resemble that of a free charge. Thus, the presence of a charge in the cavity fundamentally alters the electric field dynamics.
Ajay.makhecha
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If a conductor has a cavity in it and if a charge is placed in the cavity, then will the electric field inside it be zer
 
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Ajay.makhecha said:
If a conductor has a cavity in it and if a charge is placed in the cavity, then will the electric field inside it be zer

Welcome to the PF.

The field inside the cavity will not be zero. Is there a reason that you think it would be zero?
 
Actually I just started learning electrostatics. In our texts it is mentioned that electric field inside a conductor must be 0. But nothing is mentioned if it has a charge inside it. So I just asked out of curiosity. Btw can you say why it won't be zero?
 
Ajay.makhecha said:
Actually I just started learning electrostatics. In our texts it is mentioned that electric field inside a conductor must be 0. But nothing is mentioned if it has a charge inside it. So I just asked out of curiosity. Btw can you say why it won't be zero?

(I fixed "u" to "you" in your post -- we don't use text speak at the PF :smile: )

There is a field because there is a charge (source of E-field) with no conductor shielding it from the space inside the cavity.
 
"Inside a conductor" in this case should be read as inside the volume actually occupied by the conductor.
It can also mean a hollow space surrounded by a conductor, in which the field is not necessarily zero.
Suppose a charge q is in the hollow space
On the inner and outer surfaces charges (-q and +q) are distributed such that the electric field inside the metal is cancelled.
Outside the metal a field exists due to the outer surface charge distribution of +q. If the conductor and the cavity are spherical and concentric,
this field will be equal to the field of a free charge.
 
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