Ask question

Ask question

All categories

2 years ago

5

A baseball hits a car, breaking its window and triggering its alarm which sounds at a frequency of 1210 Hz. What frequency (in H

z) is heard by a boy on a bicycle riding away from the car at 8.25 m/s? Take the speed of sound to be 343 m/s.

1 answer:

IRINA_888 [86]2 years ago

8 0

Answer:

The frequency of sound heard by the boy is 1181 Hz.

Explanation:

Given that,

Frequency of sound from alarm $f_{0} = 1210\ Hz$

Speed = -8.25 m/s

Negative sign show the boy riding away from the car

Speed of sound = 343

We need to calculate the heard frequency

Using formula of frequency

$f = f_{0}(\dfrac{v+v_{0}}{v-v_{s}})$

Where, $f_{0}$ = frequency of source

$v_{0}$ = speed of observer

$v_{s}$ = speed of source

$v$ = speed of sound

Put the value into the formula

$f=1210\times\dfrac{343+(-8.25)}{343-0}$

here, source is at rest

$f=1180.8\ Hz$

$f=1181\ Hz$

Hence, The frequency of sound heard by the boy is 1181 Hz.

You might be interested in

Which statement best explains the relationship between the wavelengths and the frequencies of all the waves in the electromagnet

sukhopar [10]

Which statement best explains the relationship between the wavelength and the frequencies of all the waves in the electromagnetic spectrum?
B. <span>The higher the frequency of the waves, the lower their wavelength is.</span>

4 0

2 years ago

Karissa is conducting an experiment on the amount of salt that dissolves in water at different temperatures. She repeats her tes

Oksanka [162]

Answer:

idk

Explanation:

3 0

2 years ago

Read 2 more answers

A Labrador retriever breeder needs to determine if three male pups who were born to Sadie, his black Labrador retriever, are the

Novosadov [1.4K]

Answer: The things we know are:

Sadie, the mother, is a black labrador.

Sam, the possible father, is a yellow labrador.

Discarding things such as a scientific indagation, the breeder could look for traits in the pups.

For example, yellow is recessive against black, so if the pups are yellow, there is probable that the father is Sam, none the less, if the pups are black there is also the possibility where Sam is the father, just in this case the color genes that the pups received are the ones of the mother.

A good starting point is looking at the color, the posture, and things like that.

In the end, these things are only statistics, there is not any determination here, the only real (scientific) determinative process is a paternity test.

7 0

2 years ago

You throw a tennis ball (mass 0.0570 kg) vertically upward. It leaves your hand moving at 15.0 m/s. Air resistance cannot be neg

Deffense [45]

Answer:195 J

Explanation:

Given

mass of ball $m=0.0570\ kg$

ball leaves the hand with $u=15\ m/s$

maximum height reached by ball $h=8\ m$

Initial Mechanical energy when ball just leaves the hand

$M.E._1=(P.E.+K.E.)_1$

$M.E._1=(mgh)_1+(\frac{1}{2}mv^2)_1$

considering hand to be datum so h_1=0[/tex]

so Potential energy at ground is zero

$M.E._1=\frac{1}{2}\times m\times (15)^2$

$M.E._1=6.41\ J$

Mechanical Energy at highest point

$(M.E.)_2=(P.E.+K.E.)_2$

at highest Point velocity is zero

$(M.E.)_2=mgh_2+0$

$(M.E.)_2=0.0570\times 9.8\times 8$

$(M.E.)_2=4.46\ J$

Decrease in Mechanical energy

$(M.E.)_1-(M.E.)_2=6.41-4.46$

$(M.E.)_1-(M.E.)_2=1.95\ J$

3 0

2 years ago

The weight of Earth's atmosphere exerts an average pressure of 1.01 ✕ 105 Pa on the ground at sea level. Use the definition of p

zloy xaker [14]

Answer:

The weight of Earth's atmosphere exert is $516.6\times10^{17}\ N$

Explanation:

Given that,

Average pressure $P=1.01\times10^{5}\ Pa$

Radius of earth $R_{E}=6.38\times10^{6}\ m$

Pressure :

Pressure is equal to the force upon area.

We need to calculate the weight of earth's atmosphere

Using formula of pressure

$P=\dfrac{F}{A}$

$F=PA$

$F=P\times 4\pi\times R_{E}^2$

Where, P = pressure

A = area

Put the value into the formula

$F=1.01\times10^{5}\times4\times\pi\times(6.38\times10^{6})^2$

$F=516.6\times10^{17}\ N$

Hence, The weight of Earth's atmosphere exert is $516.6\times10^{17}\ N$

8 0

2 years ago

Read 2 more answers