Home
Class 12
PHYSICS
An e.m. wave travels in vacuum along z d...

An e.m. wave travels in vacuum along z direction:
`vecE=(E_1hati+E_2hatj)cos (kz-omega)`. Choose the correct option from the following :

A

The associated magnetic field is given as ` vecB = 1/c (E_1 hati + E_2 hatj ) cos (kz - omega t ) `

B

the associated magnetic field is given as ` vecB = 1/c ( E_1 hati -E_2 hatj ) cos (kz - omega t).`

C

The given electromagnetic field is circularly polarised .

D

the given electromagnetic wave is plane polarised

Text Solution

Verified by Experts

The correct Answer is:
A, D
The electric field vector is given by
`vecE = ( E_1 hati +E_2 hatj ) cos ( kz - omega t)`
the associated magnetic field vector will be thus given by
` vecB = ( vecE )/(c )= (( E_1 hati +E_2 hatj)/( c) ) cos ( kz - omega t)`
hence , option (a) is correct .
when electric field and magnetic fields are in same phase then wave is called plane polarised . when there is a plane difference of ` pi //2` between electric and magnetic field then wave is called circularly polarised . IF we select option (a) as correct then given wave is plane polarised
the correct options are (a) and (d) .
Promotional Banner

Topper's Solved these Questions

  • ELECTROMAGNETIC WAVES

    MODERN PUBLICATION|Exercise NCERT FILE ( NCERT EXEMPLAR PROBLEMS SUBJECTIVE QUESTIONS ) ( VERY SHORT ANSWER TYPE QUESTIONS )|7 Videos

  • ELECTROMAGNETIC WAVES

    MODERN PUBLICATION|Exercise NCERT FILE ( NCERT EXEMPLAR PROBLEMS SUBJECTIVE QUESTIONS ) ( SHORT ANSWER TYPE QUESTIONS )|7 Videos

  • ELECTROMAGNETIC WAVES

    MODERN PUBLICATION|Exercise NCERT FILE ( NCERT ADDITIONAL EXERCISES )|4 Videos

  • ELECTROMAGNETIC INDUCTION

    MODERN PUBLICATION|Exercise CHAPTER PRACTICE TEST FOR BOARD EXAMINATION|14 Videos

  • ELECTROSTATIC POTENTIAL AND CAPACITANCE

    MODERN PUBLICATION|Exercise Chapter Practice Test|9 Videos

Similar Questions

Explore conceptually related problems

An e.m. wave trevels in vacuum along z direction: vecE=(E_1hati+E_2hatj)cos (kz-omegat) . Choose the correct option from the following :

An electromagnetic wave travelling along z-axis is given as E=E_(0) " cos "(kz- omegat). Choose the correct options from the following

choose e correct option w.r.t. leg- haemoglobin

As the e.m waves travel in free spaces

Identify A to E choose the correct option accordingly .

A plane electromagnetic wave travels in vacuum along z-direction. What can you say about the direction of electric and magnetic field vectors?

A plane EM wave travelling along z direction is described by E=E_0sin (kz-omegat) hati and B=B_0 sin (kz-omegat)hatj . show that (i) The average energy density of the wave is given by u_(av)=1/4 epsilon_0 E_0^2+1/4 (B_0^2)/(mu_0) . (ii) The time averaged intensity of the wave is given by I_(av)=1/2 cepsilon_0E_0^2 .