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Andrej [43]
3 years ago
7

A speaker fixed to a moving platform moves toward a wall, emitting a steady sound with a frequency of 235 Hz . A person on the p

latform right next to the speaker detects the sound waves reflected off the wall and those emitted by the speaker. How fast should the platform move for the person to detect a beat frequency of 6.00 Hz ?
Take the speed of sound to be 344 m/s .
Physics
1 answer:
Anvisha [2.4K]3 years ago
5 0

Answer:

vr = 4.336 m/s

Explanation:

We are given that;

Beat frequency is 6Hz

Speed of sound = 344 m/s

Now,

Reflective Doppler frequency; f = 235 + 6 = 241 Hz

We can calculate the observed frequency if both the source sound and the observer are moving towards each other. In this case, the formula is:

f = fo[(c + vr)/(c + vs)]

Where;

ƒ = observed frequency

c = speed of sound

vs = velocity of source (negative if it’s moving toward the observer)

ƒ0 = emitted frequency of source

Since it’s moving toward the observer, thus we can rewrite equation as;

f = fo[(c + vr)/(c - vs)]

We have that;

fo = 235 , f = 241 , c = 344 , vr=vs

Thus,

241 = 235[(344+vr)/(344-vr)]

241(344 - vr)= 235(344 + vr)

82904 - 241vr = 80840 + 235vr

82904 - 80840 = 241vr + 235vr

2064 = 476 vr

vr = 2064/476

vr = 4.336 m/s

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kramer

Answer:

0.2s

Explanation:

Given parameters:

Speed  = 25m/s

Distance  = 5m

Unknown:

Time taken for Juan to get to his work  = ?

Solution:

To solve this problem we use the relationship below:

 

   Speed  = \frac{distance}{time}  

  Time  =  \frac{distance }{speed}  

So;

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Explanation:

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The severity of a fall depends on your speed when you strike the ground. All factors but the acceleration from gravity being the
Diano4ka-milaya [45]

Answer:

<em>The object could fall from six times the original height and still be safe</em>

Explanation:

<u>Free Falling</u>

When an object is released from rest in free air (no friction), the motion is completely dependant on the acceleration of gravity g.

If we drop an object of mass m near the Earth surface from a height h, it has initial mechanical energy of

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