PHYSICS 5B Lecture Notes - Lecture 17: Sonic Boom, Radio Wave, Mlh1

Compute the wavelength of the radio waves from the followingstations.
(a) an AM station operating at a frequency of 635 kHz (in m)
(b) an FM station with a frequency of 95.5 MHz (in m)

Compute the wavelength of an X-ray with a frequency of 4 1018 Hz.in nm

What is the frequency of blue light that has a wavelength of 448nm? in Hz

An electromagnetic wave has a wavelength of 6.12 10-6 m. In whatregion of the EM spectrum is this radiation? Give the frequency ofthe electromagnetic wave to support your answer. in Hz

Compute the wavelength in air of ultrasound with a frequency of 54kHz if the speed of sound is 344 m/s. in m


During a thunderstorm, 4.9 s elapses between observing a lightningflash and hearing the resulting thunder. Approximately how far awayin km and mi was the lightning flash? in km? in mi?

 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.

1. Please solve this as early as possible.
   
   (1). Light waves are electromagnetic waves that traval at 3. 00 x 10^8 m/s. The aye Is most sensitive to light having a wavelength of 5. 50 x 10^-7m. {a} Find the frequency of this light wave Hz = 
   
   Find  the frequency  of this light wave (HZ)
   and its period(S).
   
   2.The distance between two successive minima of a transverse wave is 3.00 m. Five full crest Intervals of the wave pass  given point along the direction of travel every 
   
   14.2 s.
   
   (a) Find the frequency of the wave Hz 
   
   (b} Find the wave speed m/s 
   3.

   A harmonic wave bs traveling slong a repe It is observed that the oscillator that generates the wave completes 36.0 vibrations In 35.0 s Also, a given maximum travels 430 cm along the rope in 9.0 s What Is the wavelength in cm ?

   4.

   A bat can detect small objects, such as an insect, whose size is approximately equal to one wavelength of the sound the bat makes. If bats emit a chirp at a Frequency of

   8.54 x 10^4 Hz, and if the speed of sound in air is 343 m/s, what is the smallest Insect a bat can detect in mm ?

   5. A cork on the surface of 5 pond bobs up and down two times per second an Hippies having a wavelength of 9.50 cm .If the cork is 11.5 m fram shore, how long does it take a tipple passing the cork to reach the shore ?
     (        )S.

6. Ocean waves are traveling te the east at 4. 7 m/s with a distance of 19 m between crests. (a) With what frequency do the waves hit the front of a boat when the boat Is at anchor?
(          ) HZ 

(b) With what frequency do the waves hit the front of a boat when the boat Is moving westward at 1.5 m/s? 
 (          ) HZ

7.

A circus performer stretches s tightrope between two towers. He strikes ane end of the rope and sends a wave atong it toward the other tower He notes that It takes the

wave 0. 840 s to reach the opposite tower, 20.0 m away If s 1.00-m length of the rope has a mass of 0.260 kg, find the tension In the tightrope .
(            ) N ?.

8.  Transverse waves with a speed of 52. 0 m/s are to be produced on a stretched string A    5 .20-m length of string with a total mass of 0.0600 kg Is used. 

{a) What is the required tension in the string? 
(           )N
(b} Calculate the wave speed in the string if the tension Is 8. 00 N. 
    (             )m/s . ?

9.A wave of amplitude 0 .53 m interferes with a second wave of amplitude 0 .19 m traveling in the same direction. 

(a) What Is the largest resultant amplitude that can occur, and under what conditions will this maximum arise? 

(           ) m 

1.The two waves interfere destructively, 

2.The two waves interfere constructively. 

(b) What is the smallest resultant amplitude that cah occur, and under what conditions will this minimum arise? 
(             ) m

1.The two waves interfere destructively 

2.The two waves interfere constructively 

10.

A certain tuning fork vibrates at a frequency of 161 Hz while each tip of Its two prongs has an amplitude of 0. 724 mm .

(a) What ts the per od of this motlon?
(          )ms .

(b) Find the wavelength of the sound produced by the vibrating fork taking the speed of sound in alr to be 343 m/s.
  (          ) m .