The figure shows a simplified circuit for a photographic flash unit. This circui
ID: 2051961 • Letter: T
Question
The figure shows a simplified circuit for a photographic flash unit. This circuit consists of a 9.0-V battery, a 50.0 k resistor, a 140 F capacitor, a flashbulb, and two switches. Initially the capacitor is uncharged and the two switches are open. To charge the unit, the switch S1 is closed; to fire the flash, switch S2 (which is connected to the camera's shutter) is closed. How long does it take to charge the capacitor to 5.0 V?
The figure shows a simplified circuit for a photographic flash unit. This circuit consists of a 9.0 - V battery, a 50.0 k omega resistor, a 140 muF capacitor, a flashbulb, and two switches. Initially the capacitor is uncharged and the two switches are open. To charge the unit, the switch S1 is closed; to fire the flash, switch S2 (which is connected to the camera's shutter) is closed. How long does it take to charge the capacitor to 5.0 V?Explanation / Answer
Assuming you mean "charge the capacitor to 5 volts"
voltage on a cap, charging
v = v[1–e^(–t/RC)]
RC = 50k x 140µF = 7 sec
5 = 9[1–e^(–t/7)]
0.555 = 1–e^(–t/7)
e^(–t/7) = 0.444
ln both sides
–t/7 = -0.811
t = 5.68 seconds
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.