Answer:
a) 361.7 Hz
b) 318.1 Hz
c) 29.3 m/s
Explanation:
a) Speed of sound in 20 degrees celcius is 343 m/s.
Use v=wavelength*frequency to find wavelength.
343=wavelength*340
wavelegth=1.009 meters
Relative speed of waves to observer A = 343+22 = 365 m/s
Plug it back in.
365=1.009*F
F=361.7 Hz
b) Relative speed of waves to observer B = 343-22 = 321 m/s
Plug it back in.
321=1.009*F
F=318.1 Hz
c) STATIONARY CAR, so 369Hz=v/1.009. v=372.3, 372.3-343=29.3m/s!
<h3><u>Answer;</u></h3>
= 75 %
<h3><u>Explanation</u>;</h3>
To measure efficiency of a machine, compare the work output to work input.
Efficiency = Work output/ work output × 100 %
= 300/400 × 100
= 75 %
A boiling pot of water (the water travels in a current throughout the pot), a hot air balloon (hot air rises, making the balloon rise) , and cup of a steaming, hot liquid (hot air rises, creating steam) are all situations where convection occurs.
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The answer for the first question is 1) A letter Is to a word
And the answer for question 2 is C