A parallel-plate capacitor of capacitance q is made using two gold plates. Another parallel-plate capacitor of capacitance C2 is made using two aluminium plates with same plate separation, and all the four plates are of same area. If pg and pa are respect

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Q: 29 (CDS-I/2017)
A parallel-plate capacitor of capacitance q is made using two gold plates. Another parallel-plate capacitor of capacitance C2 is made using two aluminium plates with same plate separation, and all the four plates are of same area. If pg and pa are respectively the electrical resistivities of gold and aluminium, then which one of the following relations is correct?

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,3,7,2,2,3,3

keywords: 

{'plate capacitor': [0, 0, 0, 1], 'capacitance c2': [0, 0, 0, 1], 'same plate separation': [0, 0, 0, 1], 'aluminium plates': [0, 0, 0, 1], 'electrical resistivities': [0, 0, 0, 1], 'gold plates': [0, 0, 0, 1], 'plates': [0, 0, 1, 4], 'aluminium': [1, 0, 3, 2], 'c2': [0, 0, 0, 1], 'relations': [1, 0, 2, 6]}

Option 1 suggests that the capacitance of the capacitor with gold plates, q, would be greater than the capacitance of the capacitor with aluminum plates, C2. This is incorrect because the capacitance of a parallel-plate capacitor is determined by the formula C=q/V, where V is the voltage across the plates and q is the charge stored in the plates. The area of the plates, the distance between them, and the dielectric constant of the material between the plates all affect the capacitance, but not the material of the plates. Therefore, the material of the plates (gold or aluminum) does not affect the capacitance.

Option 2 suggests that the capacitance of the capacitor with aluminum plates, C2, would be greater than the capacitance of the capacitor with gold plates, q. This is incorrect for the same reasons explained in Option 1.

Option 3 suggests that the product of q and the electrical resistivity of aluminum (pa) would be equal to the product of C2 and the electrical resistivity of gold (pg). This is also incorrect because capacitance and electrical resistivity are different properties of a material and they are not directly related to each other.

Option 4 states that q is equal to C2. This is the