The Following Are Positioned in Sequence: a Source of a Beam

question 13

Multiple Choice

The following are positioned in sequence: A source of a beam of natural light of intensity I₀; three ideal polarizers A,B,and C; and an observer.Polarizer axis angles are measured clockwise from the vertical,from the perspective of the observer.The axis angle of polarizer A is set at 0° (vertical) ,and the axis angle of polarizer C is set at 50°.Polarizer B is set so that the beam intensity is zero at the observer.Which of the following pairs of angles are possible axis angle settings of polarizer B?

• A) 40° and 90°
• B) 40° and 130°
• C) 40° and 140°
• D) 90° and 130°
• E) 90° and 140°

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Definitions:

Cell-Mediated Immunity

An immune response that does not involve antibodies but rather the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.

Extracellular Antigens

Antigens that exist outside the cells, which can trigger an immune response in the body.

Antibody-Mediated Immunity

A form of immunity that involves the production of antibodies by B cells in response to antigens, playing a crucial role in targeting and neutralizing foreign invaders.

Cell-Mediated Immunity

The aspect of the immune response that involves the activation of certain immune cells to fight off pathogens, rather than the production of antibodies.