Energy Density and Intensity

JEE Main Physics · Electromagnetic Waves · 15 questions, latest first

• A point light source emits E.M. waves in free space. A detector, placed at a distance of L m, measures the intensity as I_o. The…20266 April, Shift 1 · Q40
• A point source is kept at the center of a spherically enclosed detector. If the volume of the detector increased by 8 times, the…202624 January, Shift 2 · Q38
• The equation of the electric field of an electromagnetic wave propagating through free space is given by: E=√377 sin (6.27 × 10^3…202623 January, Shift 1 · Q48
• A laser beam has intensity of 4.0 × 10^14 W / m^2. The amplitude of magnetic field associated with beam is ____ T. (Take ε_o=8.85…202622 January, Shift 2 · Q39
• Due to presence of an em-wave whose electric component is given by E=100 sin (ω t-kx) NC^-1, a cylinder of length 200 cm holds…202528 January, Shift 1 · Q40
• In the given electromagnetic wave E_y=600 sin (ω t-kx) Vm^-1, intensity of the associated light beam is (in W / m^2: (Given ε_0=9…20246 April, Shift 2 · Q45
• Given below are two statements: Statement I: Electromagnetic waves carry energy as they travel through space and this energy is…202431 January, Shift 2 · Q44
• In a plane EM wave, the electric field oscillates sinusoidally at a frequency of 5 × 10^10 Hz and an amplitude of 50 Vm^-1. The…202431 January, Shift 1 · Q44
• A plane electromagnetic wave propagating in x -direction is described by E_y=(200 Vm^-1) sin [1.5 × 10^7 t-0.05 x]; The intensity…202427 January, Shift 1 · Q44
• The electric field in an electromagnetic wave is given as E=20 sin ω(t-x/c) j NC^-1 where ω and c are angular frequency and…202311 April, Shift 1 · Q37
• The energy of an electromagnetic wave contained in a small volume oscillates with202310 April, Shift 1 · Q48
• The energy density associated with electric field E and magnetic field B of an electromagnetic wave in free space is given by (…20236 April, Shift 2 · Q46
• For the plane electromagnetic wave given by E=E_0 sin (ω t-kx) and B=B_0 sin (ω t-kx), the ratio of average electric energy…20236 April, Shift 1 · Q37
• The ratio of average electric energy density and total average energy density of electromagnetic wave is:20231 February, Shift 2 · Q15
• A point source of 100 W emits light with 5 % efficiency. At a distance of 5 m from the source, the intensity produced by the…202330 January, Shift 2 · Q15