Electromagnetic Waves — Physics STD 12 Science — Question

Two identical circular wires P and Q each of radius R and carrying current 'I' are kept in perpendicular planes such that they have a common centre as shown in the figure. Find the magnitude and direction of the net magnetic field at the common centre of the two coils.

A dbuteron and an alpha particle are accelerated with the same accelerating potential. Which one of the two has:

1. Greater value of de-Broglie wavelength, associated with it and
2. Less kinetic energy? Explain.

Because of the friction between the water in oceans with the earth's surface, the rotational kinetic energy of the earth is continuously decreasing. If the earth's angular speed decreases by 0.0016rad/ day in 100 years, find the average torque of the friction on the earth. Radius of the earth is 6400km and its mass is 6.0 × 10²⁴kg.

A positive charge q is placed in front of a conducting solid cube at a distance d from its centre. Find the electric field at the centre of the cube due to the charges appearing on its surface.

A car moving at 40km/h is to be stopped by applying brakes in the next 4.0m. If the car weighs 2000kg, what average force must be applied on it?

A test charge q is made to move in the electric field of a point charge Q along two different closed paths Fig. First path has sections along and perpendicular to lines of electric field. Second path is a rectangular loop of the same area as the first loop. How does the work done compare in the two cases?

What is rms value (root mean square)?
Derive the equation of rms values of voltage and current?

Derive the condition of Constructive and destructive interference in terms of the phase difference.

Considering the case of a parallel plate capacitor being charged, show how one is required to generalize Ampere’s circuital law to include the term due to displacement current.