Kahoot questions for Exam 2 preparation


Answers will appear at the bottom.  Thanks for playing today.

1.       What is the difference between mechanical waves and EM waves?
Mechanical waves require a medium
Mechanical waves travel at the speed of light
EM waves travel at the speed of sound
EM waves cannot travel through a medium

2.       What is the frequency of a note that is one octave above 50 Hz?
51, 75, 200, 100

3.       Which is faster, the speed of light or the speed of sound?
Speed of sound
Depends on the type of light
Speed of light
They are equal

4.       WTMD is found at 89.7 on the FM dial. What does this number represent?
Speed
Frequency
Wavelength
It has no meaning

5.       To find the frequency of the immediately adjacent key on the piano, multiply the frequency by:
2, 4, 1, 1.059

6.       What does this image represent?  (Flashlight hitting mirror)
Refraction
Reflection
Diffraction
Polarization

7.       Which region is more optically dense?  (light ray entering from above into a blue region; light ray bends toward normal line)
Blue area below
White area above
They are both the same
There is not enough information to tell

8.       When light goes from air to glass, it:
Stays the same speed
Speeds up
Slows down
Stops

9.       If the lens shown is glass, are the light rays following a possible path?  (Concave lens is depicted with rays diverging outward.)
Yes
No
Depends on the type of glass

10.   In this Doppler effect image, where would an observer measure the greatest frequency?  (Concentric circles, bunched up on the right)
On the right
On the left
Where the sound is being emitted
It’s the same everywhere

11.   To calculate the wavelength of a 440 Hz sound wave traveling at 340 m/s, calculate:
340 x 440
340 / 440
440 / 340
340 + 440

12.   On a moving airplane wing, where the air pressure greatest?
Above the wing
Below the wing
Inside the wing
It is the same everywhere

13.   What does this symbol represent? (The symbol is lambda.) 
Speed
Frequency
Wavelength
Amplitude

14.   What is the correct unit for frequency?
Meters
Seconds
Meters per second
hertz

15.   Distant galaxies are red shifted. This means:
They are rotating
Moving away from us
Moving toward us
Not moving

16.   The focal point is where:
Light rays always meet
Light rays never meet
Light rays meet if they were initially parallel
Light rays stop

17.   Light rays through a curved mirror or lens:
Always meet at the same point
Meet at different points, depending on where the object is
Never cross

18.   Moving from radio waves to gamma rays along the EM spectrum:
Frequency increases
Wavelength decreases
Speed (in a vacuum) stays the same
All of these are true

19.   Which path is possible? 
4 pictures were shown – only 1 was possible.  Remember how refraction works.

20.   Why do prisms break up light into colors?
This is not true – it is a myth
Because each color in white light refracts differently
Because glass is less dense than air
Because different colors have different speeds in a vacuum


ANSWERS


Kahoot questions for Exam 2 preparation.  Sorry about the poor (quickly done) formatting.

1.      
Mechanical waves require a medium


2.       100

3.       
Speed of light

 
4.     
Frequency


5.       1.059

6.       
Reflection


7.     
Blue area below


8.       
Slows down

9.  
Yes

10.  
On the right


11.
340 / 440


12.  
Below the wing


13.   
Wavelength


14.   
hertz

15.   
Moving away from us


16.   
Light rays meet if they were initially parallel

17.  
Meet at different points, depending on where the object is

18.   
All of these are true

19.   

20.  
Because each color in white light refracts differently



 




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