Which of the following combinations should be selected for better tuning of an L-C-R circuit used for communication?
Option with highest quality factor sould be chosen as most appropriate answer.
Q = 1/R√L/C
An electron is moving in a circular path under the influence of a transverse magnetic field of 3.57 × 10–2 T. If the value of e/m is 1.76 × 1011 C/kg, the frequency of revolution of the electron is :
A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in equilibrium state. The energy required to rotate it by 60º is W. Now the torque required to keep the magnet in this new position is :
A long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent into a circular coil of n turns. The magnetic field at the centre of this coil of n turns will be :
A filament bulb (500 W, 100 V) is to be used in a 230 V main suply. When a resistance R is connected in series, it works perfectly and the bulb consumes 500 W. The value of R is :
The potential difference (VA – VB) between the points A and B in the given figure is :
