Electromagnetic Waves Test

Result

Electromagnetic Waves Test - 37

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

If the magnetic field of a plane electromagnetic wave is given by (The speed of light $$= 3\times 10^{8}/ m/s) B = 100\times 10^{-6} \sin \left [2\pi \times 2\times 10^{15} \left (t - \dfrac {x}{c}\right )\right ]$$ then the maximum electric field associated with it is

A
$$4\times 10^{4} N/C$$

B
$$4.5\times 10^{4} N/C$$

C
$$6\times 10^{4} N/C$$

D
$$3\times 10^{4} N/C$$

Solution

$$E_{0} = B_{0}\times c$$
$$= 100\times 10^{-6} \times 3\times 10^{8}$$
$$= 3\times 10^{4} N/C$$
$$\therefore$$ correct answer is $$3\times 10^{4} N/C$$.
Question 2
1 / -0

A gas of identical hydrogen like atoms has some atoms in ground state and some atoms in a particular excited state and there are no atoms in any other energy level. The atoms of the gas make transition to a higher state by absorbing monochromatic light of wavelength $$304 \mathring A $$. subsequently, the atoms emit radiation of only six different photon energies. Some of emitted photons have wavelength $$304 \mathring A $$, some have wavelength more and some have less than $$304 \mathring A $$ ( Take $$hc = 12420 eV - \mathring A $$). Find the principal quantum number of the initially excited state.

A
1

B
2

C
3

D
4

Solution
Question 3
1 / -0

A gas of identical hydrogen like atoms has some atoms in ground state and some atoms in a particular excited state and there are no atoms in any other energy level. The atoms of the gas make transition to a higher state by absorbing monochromatic light of wavelength $$304 \mathring A $$. subsequently, the atoms emit radiation of only six different photon energies. Some of emitted photons have wavelength $$304 \mathring A $$, some have wavelength more and some have less than $$304 \mathring A $$ ( Take $$hc = 12420 eV - \mathring A $$). Find the principal quantum number of the initially excited state.

A
1

B
2

C
3

D
4

Solution
Question 4
1 / -0

An EM wave radiates outwars from a dipole antenna, with $$
E_{0}
$$ as the amplitude of its electric field vector. The electric field $$
E_{0}
$$ which transports significant energy from the source falls off as

A
$$

\dfrac{1}{r^{3}}

$$

B
$$

\dfrac{1}{r^{2}}

$$

C
$$

\dfrac{1}{r}

$$

D
remains constant

Solution
Question 5
1 / -0

The displacement current is given by the expression

A
$$\mu_0\epsilon_0$$

B
$$\mu_0\epsilon_0\cfrac{d\phi_E}{dt}$$

C
$$\epsilon_0\cfrac{d\phi_E}{dt}$$

D
$$\mu_0\left(1+\epsilon_0\cfrac{d\phi_E}{dt}\right)$$

Solution
Question 6
1 / -0

Which of the following relation is correct

A
$$\sqrt {\in_{0}}E_{0}=\sqrt {\mu_{0}}B_{0}$$

B
$$\sqrt {\mu_{0}\in_{0}}E_{0}=B_{0}$$

C
$$B_{0}=\sqrt {\mu_{0}\in_{0}}E_{0}$$

D
$$\sqrt {\mu_{0}}_{0}E_{0}=\sqrt {\in_{0}}B_{0}$$

Solution
Question 7
1 / -0

Displacement current flows

A
Between capacitors plates and wire of circuit

B
In between capacitor plates only

C
In resistance of circuit only

D
none of these

Solution
Question 8
1 / -0

Direction of propagation of wave means :

A
flow of wave

B
direction in which energy of wave is moving

C
direction of vivration

D
direction of electric field

Solution
Question 9
1 / -0

A plane electromagnetic wave propagation in the x-direction has a wavelength of $$5.0$$ mm. The electric field is in the y-direction and its maximum magnitude is $$30V/m$$. Find equation for the electric field as a field as a function of x and t.

A
$$E= 30 sin[12\pi \times 10^{10}t-400\pi x]$$

B
$$E= 15 sin[400\pi \times -12\pi x 10^{10}]$$

C
$$E= 30 sin[48\pi \times 10^{10}t-1200\pi x]$$

D
$$E= 15 sin[48\pi \times 10^{10}t-1200\pi x]$$

Solution
Question 10
1 / -0

A gas of identical hydrogen like atoms has some atoms in ground state and some atoms in a particular excited state and there are no atoms in any other energy level. The atoms of the gas make transition to a higher state by absorbing monochromatic light of wavelength $$304 \mathring A $$. subsequently, the atoms emit radiation of only six different photon energies. Some of emitted photons have wavelength $$304 \mathring A $$, some have wavelength more and some have less than $$304 \mathring A $$ ( Take $$hc = 12420 eV - \mathring A $$)
Find the principal quantum number of the initially excited state.

A
1

B
2

C
3

D
4

Solution