# Physics

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3. What mathematical expression tells you to what percentage the charge is after n t1/2's?
(All these should be multiplied by 100% to obtain the percentage.)
2- n
V*C
e-t/τ
R*C
1 - 2^- n ((((((((((( I think this is right what do you think)))))))))))
R*C*ln2

4. What expression tells you what percentage is left to be charged at the same n t1/2's?
(All these should be multiplied by 100% to obtain the percentage.)
R*C
R*C*ln2
( 2n - 1 ) 2^- n ((((((((((( I think this is right what do you think)))))))))))
1 - 2- n
V*C
1-e-t/τ
2- n
5. Given a resistance of 165 Ω and a capacitance of 335 μF,
what is t1/2?
t1/2 = [milliseconds]
(Answer to one tenth of a millisecond or N/A if there is no answer.)

t1/2 = 38.3 Now I found this by doing this: 165*335 =55275 then 55275*Ln(2)=38313.71[milliseconds]

I don't know if this is right or not?

6. Given a resistance of 165 Ω and a capacitance of 335 μF,
what is the time constant τ (tau)?
τ (tau) = [units reserved for next question.]
Use normal unit for this answer not milli nor micro units.

τ (tau) = 55.3 I found this by simply multiplying 165*335 =55275
Use normal unit for this answer not milli nor micro units.

7. What are the units of τ?
F
μF
second ((((((I think this is the answer what do you think))))))))
Volt
Amp
Coulomb
Volt/Amp
Coulomb Volt
Ω

8. You have an RC circuit and you measure the "zero" voltage to actually be -2.595 [Volts].
The peak voltage is measured to be 8.502 [Volts].
At what voltage value will you look for t5 = time stamp for 31/32 total charge?
[Volts] (((((((Please show me some steps on this i am extremely confused on this one.))))))))))))))))))))))))))))))))
(Use three significant figures or N/A if there is no answer.)

• Physics - ,

5. t(1/2) = Ln2 * 0.165k Ohm * 335uF = 38.3 milliseconds.

6. tau = RC = 165 Ohm * 335*10^-6F =
55275*10^-6 = 5.53*10^-2 Seconds.

7. Seconds.

• Physics - ,

question 3.. you are correct
question 4 you are not correct