Unit:-8 Waves Numerical problems.

      

      NUMERICAL PROBLEMS

                                       8.1

The wavelength of the signals from a radio transmitter is 1500m and the frequency is 200kHz . What is the wavelength for a transmitter operating at 1000kHz and with what speed the radio waves travel?

SOLUTION:-

  

Data:

        λ1= 1500

        F1=200,000Hz              ∴ where K=1000

        F2=1000,000Hz            ∴ where K=1000

 (1)      V=  F1  λ1    |   (2)    λ = ?

     V=200,000×1500 |         V=F2  λ2

     V=3×108ms-1     |  ⇒    λ2=    V    

                             |                         F2

                                    |     λ2  =   3×108    

                                |             1000,000 

                                  |      λ2=300m

...............COMPLETE................

                                   8.7   

  Two tuning fork exhibit beats at a beat frequency of 3Hz .The frequency of one fork is 256Hz .Its frequency is then lowered slightly by adding a bit wax to one of its prong.The two forks then exhibit a beat frequency of 1Hz. Determine the frequency of  the second tuning fork.

SOLUTION:-

Data:

          n=3Hz

       F1=256Hz

       F2=?

   ±n =F1-F2

   ±3 =256-F2

     F2=256±3

 F2=256+3      ;   F2 =256-3

 F2=259 ×     ;;    F2=253✔

...............COMPLETE................