What is meant by " Loudness is proportional to the square of amplitude of the vibration producing the sound . For eg: If the amplitude becomes twice ,the Loudness increases by a factor of 4" ?I can't understand the meaning.
a charged is placed at the centre of a sphere radius 'r'. If the charge is moved through a distance of r/2, how does the flux through the surface change?
A ring of radius R having a linear charge density moves R ng the switch. towards a solid imaginary sphere of radius 2 ofring passes through the centre of sphere. The axis of the ring is perpendicular to the line joining the centres of the ring and the sphere.