Electrostatics physics question, by checking my answers

AI Thread Summary
The discussion revolves around solving various electrostatics and circuit problems. The first question calculates the charge flow from a calculator operating at 0.20 mA for 20 minutes, yielding a result of 2.4 x 10^-2 C. The second question addresses the change in resistance when the radius of a wire is doubled, with an answer of 0.6 x 10^2 Ohms. The third question finds that each of three identical resistors in parallel has a resistance of 4 Ohms, while the fourth question determines that the unknown resistor in a parallel circuit with a 10 Ohm resistor and a total resistance of 6 Ohms is 15 Ohms. The final question remains unanswered, as the user seeks assistance in calculating the current for two different circuit configurations.
Roro312
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Homework Statement



1. suppose that your calculator requires .20mA to operate and will be on for 20min while you solve this problem. What quantity of charge will flow during this time? I got 2.4x10^ -2

2. If the potential difference across the nerve of a frog is 85mV and its resistance is 2.5 x10^ 2 ohms. What change in resistance would result if the radius of a wire were doubled?
I got 0.6 x 10^ 2 Ohms.

3. A parallel combination of three identical resistors has a total resistance of 12 ohms. What is the resistance of each resistor? i got 4 ohms


4. 2 resistors are connected in parallel. The total resistance of the combination is known to be 6 ohms. If one of the resistors is 10 ohms, what is the value of the other? I got 15 ohms

5. A person connects a 6.0 v battery in series with a 10 ohms resistor and two 10 ohms resistors connected in parallel. In a second circuit, the person connects an identical 6 V battery to two 10 ohms resistor connected in series. Calculate the current in the first and second circuits?
I don't know how to do this one at all



Homework Equations





The Attempt at a Solution

 
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Roro312 said:

Homework Statement



1. suppose that your calculator requires .20mA to operate and will be on for 20min while you solve this problem. What quantity of charge will flow during this time? I got 2.4x10^ -2

2. If the potential difference across the nerve of a frog is 85mV and its resistance is 2.5 x10^ 2 ohms. What change in resistance would result if the radius of a wire were doubled?
I got 0.6 x 10^ 2 Ohms.

3. A parallel combination of three identical resistors has a total resistance of 12 ohms. What is the resistance of each resistor? i got 4 ohms


4. 2 resistors are connected in parallel. The total resistance of the combination is known to be 6 ohms. If one of the resistors is 10 ohms, what is the value of the other? I got 15 ohms

5. A person connects a 6.0 v battery in series with a 10 ohms resistor and two 10 ohms resistors connected in parallel. In a second circuit, the person connects an identical 6 V battery to two 10 ohms resistor connected in series. Calculate the current in the first and second circuits?
I don't know how to do this one at all



Homework Equations





The Attempt at a Solution


Can you show the equations you used for these? And your math?
 

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