Question

Gauss law cannot be used find

• A. charge
• B. r
• C. v
• D. Permittivity

Answer 1

Answer: (C)

v

Answer 2

Gauss's Law relates electric flux, electric field, enclosed charge, and permittivity of free space. It is a law of electrostatics, dealing with stationary charges and their fields.

1. Charge (Q): Can be found if electric field and surface are known.
2. r (distance): Can be found indirectly by solving for 'r' from the electric field expression derived using Gauss's Law.
3. v (velocity): Gauss's Law has no relation to motion or velocity. It cannot be used to find velocity.
4. Permittivity ($\epsilon_0$): This is a fundamental constant used in the law, not a variable to be determined by the law itself. Its value is fixed. Therefore, it cannot be "found" using Gauss's Law.

Both 'v' (velocity) and 'Permittivity' are quantities that Gauss's Law cannot be used to find. However, if a single best answer is required, 'v' (velocity) is completely outside the scope of electrostatics, while permittivity is a constant within the scope of the law. In many contexts, questions about "what a law cannot find" often refer to quantities outside its domain or fundamental constants.

The question asks what Gauss's law cannot be used to find.

It can be used to find charge (Q) and electric field (E), which depends on distance (r). Potential (V) can be found from E.

It cannot be used to find velocity (v), as it's a law of electrostatics.

It cannot be used to find permittivity ($\epsilon_0$), as it's a fundamental constant used in the law.

Given the options, and assuming 'v' refers to velocity, it is a quantity completely unrelated to the domain of Gauss's Law.