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Soloha48 [4]
3 years ago
13

Ira is concerned about his posture. He tests it by seeing how long he can hold good posture and finds that he feels the most dis

comfort in his back. What does that suggest that he needs to do?
A.
Keep a neutral spine.
B.
Place his hands on his hips.
C.
Arc his back when he walks.
D.
Tuck his chin close to his chest.
Physics
1 answer:
larisa [96]3 years ago
6 0

Answer: C

Explanation:

JUST TO SIMPLE

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Answer:

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If the police car is a stationary observer, the frequency is:

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1250=1200(\frac{v+v_{c} }{v-v_{c} } )\\1250(v-v_{c} )=1200(v+v_{c} )\\v_{c} =\frac{50*344}{2450} =7.02m/s

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f_{L} =(\frac{v+v_{p} }{v-v_{c} } )(\frac{v+v_{c} }{v-v_{p} } )f_{s} =(\frac{344+20}{344-7.02} )(\frac{344+7.02}{344-20} )*1200=1404.08Hz

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