Archives

An ac source of angular frequency ω is fed across a resistor R and a capacitor C in series. The current registered is I . If now the frequency of the source is changed to ω/3 (but maintaining the same voltage), the current in the circuit is found to be halved. The ratio of the reactance to resistance at the original frequency ω is given as √ x/5 . Find x .

The root-mean-square current Irms in the RC circuit is given by Irms = Vrms/√R2 +X2C…… (1) Here, Vrms is the root-mean-square voltage, R is the... View Article

A particle of charge q and mass m enters normally (at point P) in a region of the magnetic field with speed v. It comes out normally from Q after time T as shown in fig. The magnetic field Bis present only in the region of radius R and is uniform. Initial and final velocities are along the radial direction and they are perpendicular to each other. For this to happen, which of the following expression(s) is/are correct?

When a charged particle in motion is exposed to a magnetic field that is perpendicular to its direction of travel, we know that the particle will... View Article

As shown in the figure, AB is a rod of length 30 cm and area of cross section 1.0 cm2 and thermal conductivity 336 SI units. The ends A and B are maintained at temperatures 20degreeC and 40degreeC , respectively. A point C of this rod is connected to a box D, containing ice at 0degreeC , through a highly conducting wire of negligible heat capacity. The rate at which ice melts in the box is (assume latent heat of fusion for ice Lf= 80 cal/g)

Fourier’s law states that the negative gradient of temperature and the time rate of heat transfer is proportional to the area at right angles of... View Article