In the Figure,in the Investigation of a New Type of Optical

question 21

Multiple Choice

In the figure,in the investigation of a new type of optical fiber (index of refraction n = 1.26) ,a laser beam is incident on the flat end of a straight fiber in air.What is the maximum angle of incidence θ₁ if the beam is not to escape from the fiber?

• A)50.0°
• B)46.9°
• C)43.8°
• D)40.7°
• E)37.6°

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Definitions:

Acetylcholine

A neurotransmitter in both the central and peripheral nervous systems that plays a key role in arousal, attention, memory, and motivation.

Somatic Nervous System

A part of the peripheral nervous system that controls voluntary movements of the body through the control of skeletal muscles.

Autonomic Nervous System

The part of the nervous system that controls involuntary functions such as heart rate, digestion, and respiratory rate, divided into the sympathetic and parasympathetic systems.

Chemical Synapses

Specialized junctions through which neurons signal to each other and to non-neuronal cells, allowing the transmission of chemical messengers (neurotransmitters).