A Solid Sphere of Radius a Is Concentric with a Hollow

question 87

Multiple Choice

A solid sphere of radius a is concentric with a hollow sphere of radius b, where b > a. If the solid sphere has a charge +Q and the hollow sphere a charge of -Q, the electric field at radius r, where r < a, is which of the following, in terms of k = 4π₀) ^-1?

• A) kQ/r²
• B) kQr/a³
• C) kQ/a²
• D) kQ/b²
• E) zero

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Definitions:

Nucleotide

Organic molecules that serve as the monomers of nucleic acids like DNA and RNA, composed of a nitrogenous base, a five-carbon sugar, and one or more phosphate groups.

mRNA

Messenger RNA, a type of RNA that carries instructions from DNA in the nucleus to the ribosome, where proteins are synthesized.

5′ Cap

A modified form of guanine nucleotide added to the 5′ end of eukaryotic mRNA, important for mRNA stability and initiation of translation.

Degradation

The process by which a compound is broken down or decomposed, often into simpler substances, sometimes leading to a loss of quality or function.