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:

Distal Convoluted Tubules

Tubes in the kidney where filtration, reabsorption, and secretion occur, resulting in the formation of urine.

Proximal Convoluted Tubules

The portion of the nephron in the kidney that is responsible for reabsorbing water, ions, and nutrients from the filtrate back into the blood.

Loop of Henle

A U-shaped portion of the nephron in the kidney, crucial for concentrating urine and recovering water and sodium from the urine.

Renal Corpuscle

A structure in the kidney that includes the glomerulus and Bowman's capsule, essential for filtering blood and starting urine formation.