A capacitor is constructed from two square parallel plates with equal and opposite charges.

Sunday, 26 August 2018

12:54 AM

Machine generated alternative text: Question: Figure 1 _ A capacitor ottwo identical plates. A capacitor is constructed trom two square parallel plates with equal and opposite charges. Their area is much greater than the square ot the distance between them (the sketch is not to scale). The capacitor has a capacitance otC = 7.29"C and a potential difference between the üo plates ot IAVI = 140 V. part 1) What is the magnitude ottne charge found on the plates? C part 2) What is the change in potential energy when moving a charge q part 3) +6.57 x 10 8 C from the positive plate to the negative plate? The charge on each ot the plates is now doubled. What is the capacitance and potential difference between the plates now? IAVI Check

 

Machine generated alternative text: Incorrect answer. Note: Your answers should be correct to 3 significant figures. Feedback tor Part 1) For a capacitor, C _g_ so Q = C x IAVI. You just need to substitute into this expressiom Remember to convert C from F to F. IAVI Marks for this submissiom 0.00/0.33. This submission attracted a penalty of 0.11 Feedback tor Part 2) The change in potential energy is given by: AU - qAV. The negative plate is at a lower potential than the positive plate, so in this case AV — —140. You just need to substitute in the numbers given in the question. Marks for this submissiom 0.00/0.33. This submission attracted a penalty of 0.11 Feedback tor Part 3) You have incorrectly entered the capacitance. You have incorrectly entered the potential. The capacitance of parallel plates is given by C = -Egg d , the area and distance between the plates is not being changed so C remains the same. The potential is related to the capacitance through: Q IAVI As C did not change, and Q doubled, AV also doubled. Marks for this submissiom 0.00/0.33. This submission attracted a penalty of 0.11 A correct answer is 0.00102, which can be typed in as follows e. oe182 A correct answer —9.2e — 16, which can be typed in as follows: -g. 22-16 A correct answer 7.29, which can be typed in as follows: 7.29 A correct answer is 280, which can be typed in as follows: 288

 

 

Created with Microsoft OneNote 2016.