Please write your solutions in the blue books Shew all work in an ordeily and eg
ID: 1872935 • Letter: P
Question
Please write your solutions in the blue books Shew all work in an ordeily and egible manner s appropriate units and significant figures Simplity anwers if possible Turn in the takehome probiem with the test L Twe klentical vertical parallel plates each have an ares of 13 square centimeters One plate a charge or +3 2 microcouhombs and the other plate has a charge of 3 2 rmerocodombs. The charge is evenly distributed over the plates Between the plates hangs15 gram positively charged ball from a string that makes an angle of 25 degrees with respect to the vertical. What is the charge on the ball Side +G -a A point charge of +6.s microcoulombs is fixed in place. Another charge of-4.8 microcoulombs starts at rest a distance of 10.0 cm away from the fixed charge and is released so that it Is free to move. What is the speed of the negative charge when it is 3.0 cm from the fixed charge? Both charges have a mass of 25 milligrams 2. Be tere 0.00m 4 A 75 square micrometer area of muscle membrane has a density of sodium channels of 50 per square micrometer of surface area. When the channels open there is a rapid flow of 1000 sodium ions (each with charge te) per channel across the membrane. If the membrane has a capacitance per unit area of 1.0 microfarads per square centimeter find the voltage change across the membrane if all the sodium channels open together at once. 3.Explanation / Answer
2. initial potential energy of system,
PEi = k q1 q2 / r1
= (9 x 10^9) (6.5 x 10^-6)(-4.8 x 10^-6) / 0.10
= - 2.808 J
PEf = (9 x 10^9)(6.5 x 10^-6)(-4.8 x10^-6) / 0.03
= - 9.36J
Applying energy conservation,
PEi + KEi = PEf + KEf
- 2.808 + 0 = - 9.36 + (25 x 10^-6) v^2 / 2
v = 724 m/s .........Ans