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What is the wavelength range of visible light ?

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Important Questions on Electromagnetic Waves

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The electric field of a plane electromagnetic wave is given by
E=E0i^coskzcos(ωt)
The corresponding magnetic field B is then given by:
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Consider an electromagnetic wave propagating in vacuum. Choose the correct statement:
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An electromagnetic wave is represented by the electric filed E=E0n^sinωt+6y-8z. Taking unit vectors in x,y and z directions to be i^, j^, k^,  the directions of propagations s^, is:
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The E.M. wave with shortest wavelength among the following is
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The waves used by artificial satellites for communication purposes are
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The ratio of contributions made by the electric field and magnetic field components to the intensity of an electromagnetic wave is:
(c= speed of electromagnetic waves)
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Which colour of the light has the longest wavelength?
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If the intensity of sun light outside earth's atmosphere is 1.4 kW cm-2, the corresponding maximum electric field amplitude is, approximately (Assume μ0=4π×10-7 H m-1)
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The magnetic field in a travelling electromagnetic wave has a peak value of 20 nT. The peak value of electric field strength is :
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In an electromagnetic wave in free space the root mean square value of the electric field is Erms=6 V m-1. The peak value of the magnetic field is
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If the magnetic field of a plane electromagnetic wave is given by (The speed of light =3×108 m s-1)

B=100×10-6sin2π×2×1015t-xc then the maximum electric field associated with it is:
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A plane electromagnetic wave of frequency 30 MHz is travelling along k^ - direction. At a particular point of space and time of propagation, if the electric field is given by E=30 Volts meter-1 -i^, then the corresponding magnetic field is
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An electromagnetic wave is travelling in x-direction with electric field vector given by, Ey=E0sinkx-ωt j^. The correct expression for magnetic field vector is
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The permeability of a medium whose refractive index is 1.5 and permittivity is 4.43×10-11 F m-1 is
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The electromagnetic wave used in LASIK eye surgery is
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The amplitude of the electric field in a parallel beam of plane electromagnetic waves of intensity 53.1Wm-2 is
(Permittivity of free space =8.85×10-12C2 N-1m-2)
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During the propagation of electromagnetic wave in a particular medium :-
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The energy of the em waves is of the order of 15 keV. To which part of the spectrum does it belong?
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Out of the following options which one can be used to produce a propagating electromagnetic wave?