Offline paper
Physics · 2015
JEE Main 2015 · 2015-04-04 Offline · Q23
A red LED emits light at 0.1 watt uniformly around it. The amplitude of the electric field of the light at a distance of 1 m from the diode is:
A red LED emits light at $\displaystyle 0.1$ watt uniformly around it. The amplitude of the electric field of the light at a distance of $\displaystyle 1$ m from the diode is :
Official answer
(2)
2.$\displaystyle 45$ V/m
More from Electromagnetic Waves
- An electromagnetic wave of frequency 3 GHz enters a dielectric medium of relative electric permittivity 2.25 from vacuum. The wavelength of this wave…2021
- The electric field in an electromagnetic wave is given by E=56.5 sin ω(t-x / c) NC^-1. Find the intensity of the wave if it is propagating along x…2022
- The equation of the electric field of an electromagnetic wave propagating through free space is given by: E=√377 sin (6.27 × 10^3 t-2.09 × 10^-5 x) N…2026
- Given below are two statements: Statement I: A time varying electric field is a source of changing magnetic field and vice-versa. Thus a disturbance…2022
- Choose the correct answer from the options given below:2026
- The electric field of a plane electromagnetic wave is given by E=E_0 i cos (k z) cos (ω t) The corresponding magnetic field B is then given by:2019
- A point source of light is placed at the centre of curvature of a hemispherical surface. The source emits a power of 24 W. The radius of curvature of…2023
- Light is incident normally on a completely absorbing surface with an energy flux of 25 Wcm^-2. If the surface has an area of 25 cm^2, the momentum…2019
JEE Main 2015 Physics question, with the answer from NTA’s final answer key. Where our answers come from.