The kinetic energy possessed by a body of mass $m$ moving with a velocity $ v$ is equal to $\frac{1}{2}m{v^2}$, provided
The body moves with velocities comparable to that of light
The body moves with velocities negligible compared to the speed of light
The body moves with velocities greater than that of light
None of the above statement is correcst
Show that the radiation pressure exerted by an $EM$ wave of intensity $I$ on a surface kept in vacuum is $\frac{I}{c}$.
Figure given shows the face of a cathode-ray oscilloscope tube, as viewed from in front. $i.e.$ the electron beam is coming out normally from the plane of the paper. The electron beam passes through a region where there are electric and magnetic fields directed as shown. The deflections of the spot from the center of the screen produced by the electric field $E$ and the magnetic field $B$ separately are equal in magnitude. Which one of the diagrams below shows a possible position of the spot on the screen when both fields are operating?
A long straight wire of resistance $R$, radius $a $ and length $ l$ carries a constant current $ I.$ The Poynting vector for the wire will be
A wave is propagating in a medium of electric dielectric constant $2$ and relative magnetic permeability $50$. The wave impedance of such a medium is.....$ \Omega$
If $\overrightarrow E $ and $\overrightarrow B $ are the electric and magnetic field vectors of E.M. waves then the direction of propagation of E.M. wave is along the direction of