Saved Bookmarks
| 1. |
A 2muFcapacitor is charged to a p.d. of 60V. The charging battery is disconnected and the capacitor is connected in series with a coil of inductance 10mH, so that LC oscillations occur. What is the maximum current in the coil? Assume that the circuit contains no resistance. |
|
Answer» SOLUTION :`C = 2 xx 10^(-6) F , L = 10 xx 10^(-3) H, V = 60 V` ` (Li_m^2) /(2) = (Q^2)/(2C)` ` i_m = sqrt( (Q^2)/(LC) )` But Q = CV `therefore i_m = sqrt( (C^2V^2)/(LC) ) = sqrt( (CV^2)/(L) )` ` therefore= i_m = sqrt( (C^2 V^2)/(LC) ) = sqrt( (CV^2)/(L) ) = sqrt( (2 xx 10^(-6) xx 60 xx 60 )/(10 xx 10^(-3) ))=6 sqrt(2 xx 10^(-2) ) = 0.848 A = 848 mA` |
|