A capacitor is an arrangement for storing large amounts of electric charge and hence electric energy in a small space. The electrical capacitance of a capacitor is related to its abillity to store electric charge. We define capacity of a conductor as the ratio of charge Q given to the conductor to the rise in its potential, V i.e., `C = Q//V`. The capacity of an isolted spherical conductor of radius r is `C = 4pi in_(0) r`. In case of a parallel plate capacitor, `C = (in_(0)A)/(d)` where A is area of insulated metal plate and d is distance between the plates. Clearly, capacity depends on size of capacitor. When different capacitors are connected in series, capacity, `C_(s) = (C_(1) C_(2))/(C_(1) + C_(2))` and when capacitors are connected in parallel, `C_(p) = C_(1) + C_(2)` Read the above passage and answer the following questions : (i) From `C = (Q)/(V)`, we find that C can be increased Q or decresing V. Do you agree ? (ii) Capacity of a capacitor is fixed depending on its geometry and the medium used. Is it true ? (iii) Calculate the capacity of a condenser which when connected in series with a conductor of `12 muF` gives us a capacitance of `3 muF`. (iv) What values of life do yo+-earn from this study ?

A capacitor is an arrangement for storing large amounts of electric ch

1.	A capacitor is an arrangement for storing large amounts of electric charge and hence electric energy in a small space. The electrical capacitance of a capacitor is related to its abillity to store electric charge. We define capacity of a conductor as the ratio of charge Q given to the conductor to the rise in its potential, V i.e., `C = Q//V`. The capacity of an isolted spherical conductor of radius r is `C = 4pi in_(0) r`. In case of a parallel plate capacitor, `C = (in_(0)A)/(d)` where A is area of insulated metal plate and d is distance between the plates. Clearly, capacity depends on size of capacitor. When different capacitors are connected in series, capacity, `C_(s) = (C_(1) C_(2))/(C_(1) + C_(2))` and when capacitors are connected in parallel, `C_(p) = C_(1) + C_(2)` Read the above passage and answer the following questions : (i) From `C = (Q)/(V)`, we find that C can be increased Q or decresing V. Do you agree ? (ii) Capacity of a capacitor is fixed depending on its geometry and the medium used. Is it true ? (iii) Calculate the capacity of a condenser which when connected in series with a conductor of `12 muF` gives us a capacitance of `3 muF`. (iv) What values of life do yo+-earn from this study ?
Answer» No, we do agree. This is because capacitance C is fixed, depending on geometry fo condeaser. If we increase Q , V increases but C remains constant and vice-versa. (ii) yes, the statement is true. (iii) Here, `C_(1) = ? C_(2) = 12 muF, C_(s) = 3 muF` From `C_(s) = (C_(1) C_(2))/(C_(1) + C_(2))` `3 = (C_(1) xx 12)/(C_(1) + 12) or 12C_(1) = 3C_(1) + 36 C_(1) = 4muF` (iv) Just as capacity fo a condenser is fixed depending on its geometry, similarly capacity of a person to execuite some work is fixed depending on his buit up. Capacity increases by connecting the capacitors in parallel. exactly in the same way capacity of a group of persons can be increased when each one of them is connected to the same sources , e.g., guide or instractor. This is the implication of this concept in day to day life.

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