Severity: Warning
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Filename: drivers/Session_files_driver.php
Line Number: 176
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File: /home/answnniz/public_html/index.php
Line: 315
Function: require_once
Severity: Warning
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Filename: Session/Session.php
Line Number: 143
Backtrace:
File: /home/answnniz/public_html/index.php
Line: 315
Function: require_once
The glass core of an optical fiber has an index of refraction 1.61. The index of refraction of the cladding is 1.47. What is the maximum angle between a light ray and the wall of the core if the ray is to remain inside the core?