A resistor and a capacitor are combined in a circuit along w

A resistor and a capacitor are combined in a circuit along with a 5-volt DC power source: If C= 15 muF and R = 2.2 Kohm, how long will it take for the potential across the capacitor to reach 3.15 V once the switch S is closed? If R = 1375ohm, and the potential across the capacitor reaches 3.15 V after 3.85 times 10^-2 sec, what is the value of the capacitor C ? If C= 25 muF, and the potential across the capacitor reaches 3.15 V after 4.88 times 10^-2 sec, what is the value of the resistor R ?

Solution

A)ans: if c=15micro farad =15×10-6 F. R=2.2kilo ohm=2.2×1000=2200 ohm, time=RC. Time=2200×15×10^_6 time=0.033sec. B)ans: C=R/T. R=1375 ohm, T=3.85×10^{_2 sec. C=1375/385=3.571 ohm. C)ans: if C=25 micro farad, time=4.88×1/100 sec, R=C/T. R=0.00052 ohm}