A Container of Flint Glass (N = 1

question 20

Multiple Choice

A container of flint glass (n = 1.66) holds a small quantity of benzene (n = 1.501) . What is the critical angle for internal reflection of a ray in the liquid when it is incident on the liquid-to-glass surface?

• A) 89.5°
• B) 64.7°
• C) 41.1°
• D) The critical angle does not occur in this case.

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Definitions:

Sustained Muscle Contraction

A continuous muscle contraction without relaxation, often due to persistent stimulation.

Tetanus

A bacterial infection characterized by muscle spasms, caused by the bacterium Clostridium tetani.

Threshold Stimulus

The minimum stimulus needed to cause a depolarization of the membrane and generate an action potential in excitable cells.

Muscle Fatigue

Muscle fatigue is the decline in ability of a muscle to generate force, often experienced after prolonged activity or strain.