A common flash focus is rated at 310 mA and 2.90 V, the respective current and voltage values under functional conditions. If the resistance of the filament when cold (T-20°C) is 1.12.2, calculate its temperature when the lamp is on. The filament is made of tungsten with a coefficient of expansion x=4.5x10-3 °C-1 a). 1503 °C b) 1553 °C c) 1603 °C d) 1653°C e) 1703°C

A common flash focus is rated at 310 mA and 2.90 V, the respective current and voltage values under functional conditions. If the resistance of the filament when cold (T-20°C) is 1.12.2, calculate its temperature when the lamp is on. The filament is made of tungsten with a coefficient of expansion x=4.5x10-3 °C-1 a). 1503 °C b) 1553 °C c) 1603 °C d) 1653°C e) 1703°C

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter28: Current And Resistance

Section: Chapter Questions

Problem 58PQ

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