Question

 Please solve all of these equations  as early as possible. 

1 .

(a) The distance to a star ts approximately
  4.21 x 10^18 m. If this star were to burn out         today, in how many years would we see it

disappear?

(                            )years

(b) How long does it take sunlight to reach Earth?
(                           )minutes .

(c) How long does it take for a microwave radar signal to travel from Earth to the Moon and back? (The distance from Earth

to the Moon is 3.84 x 10^5 km }
(                    )s.

2. Which of the following statements are true regarding electromagnetic waves traveling through a vacuum?
(Select all that apply }.
1.All waves have the same wavelength. 

2.All waves have the same frequency 

3.All waves travel at 3.00 x 10° m/s 

4. The electric and magnetic flelds associated with the waves are perpendicular to each other and to the direction of wave propagation .

5.The speed of the waves depends on their frequency. 

3.What are the wavelength ranges for the following? 

(a) the AM radio band (540-1600 kHz)

  1.maximum wavelength(              ) m.

  2.minimum wavelength (              ) m.

(b)  the FM radio band (88-108 Mhz) 

maximum wavelength  (                  )m.

minimum wavelength  (                   )m.

4. What are the wavelengths of electromagnetic wave in free space that have the following frequencies? 
(a) 2. 00 x 10^19 Hz 

      (                 )pm.

(b) 7.50 x 10^9 Hz 

    (                     )cm. 

5.A diathermy machine used In physiotherapy generates electromagnetic radiation that gives the effect of "deep heat” when absorbed In tissue One assigned frequency for diathermy ts 915. 00 MHz, What is the wavelength of this radiation?
 
linear mass density (                         )m.