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प्रश्न
Speed of electromagnetic waves is the same
पर्याय
For all wavelengths
For all frequencies
In all media
For all intensities
उत्तर
For all intensities
Explanation:
In a vacuum, the speed of electromagnetic waves is constant for all intensities..
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संबंधित प्रश्न
How are electromagnetic waves produced?
About 5% of the power of a 100 W light bulb is converted to visible radiation. What is the average intensity of visible radiation
(a) at a distance of 1 m from the bulb?
(b) at a distance of 10 m?
Assume that the radiation is emitted isotropically and neglect reflection.
In the study of a photoelectric effect the graph between the stopping potential V and frequency v of the incident radiation on two different metals P and Q is shown below:
(i) Which one of the two metals has higher threshold frequency?
(ii) Determine the work function of the metal which has greater value.
(iii) Find the maximum kinetic energy of electron emitted by light of frequency 8 × 1014 Hz for this metal.
How are electric vector `(vec "E")`, magnetic vector `(vec "B")` and velocity vector `(vec "C")` oriented in an electromagnetic wave?
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In a microwave oven, the food is kept in a plastic container and the microwaves is directed towards the food. The food is cooked without melting or igniting the plastic container. Explain.
Consider the situation of the previous problem. Define displacement resistance Rd = V/idof the space between the plates, where V is the potential difference between the plates and id is the displacement current. Show that Rd varies with time as `R_d = R(e^(t"/"tau) - 1)` .
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State any one property which is common to all electromagnetic waves.
Write down Maxwell equations in integral form.
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A transmitter consists of LC circuit with an inductance of 1 μH and a capacitance of 1 μF. What is the wavelength of the electromagnetic waves it emits?
Maxwell’s displacement current is a response to inconsistency in the ______.
Dimensions of 1/(µOE0) is
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- Evaluate `oint E.dl` over the rectangular loop 1234 shown in figure.
- Evaluate `int B.ds` over the surface bounded by loop 1234.
- Use equation `oint E.dl = (-dphi_B)/(dt)` to prove `E_0/B_0` = c.
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(Given: Permittivity of vacuum ε0 = 8.85 × 10–12 C2 N–1 – m–2, speed of light in vacuum c = 3 × 108 ms-1)
For an electromagnetic wave travelling in free space, the relation between average energy densities due to electric (Ue) and magnetic (Um) fields is ______.
An electromagnetic wave is produced by a charge ______.
