When a Camera Flash Goes Off, the Batteries Immediately Begin $Q(t)=Q_{0}\left(1-e^{-t / a}\right)$

question 81

Multiple Choice

When a camera flash goes off, the batteries immediately begin to recharge the flash's capacitor, which stores electric charge given by $Q(t) =Q_{0}\left(1-e^{-t / a}\right)$ (The maximum charge capacity $Q_{0}$ is and t is measured in seconds.) How long does it take to recharge the capacitor to 90% of capacity if $a=5$ ?

• A) \(-5 \ln (1)\) seconds
• B) \(-5 \ln \left(\frac{1}{10}\right)\) seconds
• C) \(-\ln \left(\frac{4}{9}\right)\) seconds
• D) \(-5 \ln (10)\) seconds
• E) \(-5 \ln \left(\frac{9}{10}\right)\) seconds

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Definitions:

Cognitive And Behavior Therapy

A form of psychotherapy that treats problems and boosts happiness by modifying dysfunctional emotions, behaviors, and thoughts.

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The current point in time, emphasizing awareness and focus on the immediate experience.

Vivid

Producing powerful feelings or strong, clear images in the mind.

Non-rapid Eye Movement (NREM)

A period of sleep that encompasses stages 1 through 3, characterized by slower brain waves, decreased body movement, and reduced eye movement.