The frequency of a tuning fork can be found by the method shown. A long tube open at both ends is submerged in a beaker of water, and the vibrating tuning fork is placed near the top of the tube. The length L of the air column is adjusted by moving the tube vertically. The sound waves generated by the fork are reinforced when the length of the air column corresponds to one of the resonant frequencies of the tube. The smallest value for L for which a peak occurs in sound intensity is 5 cm.a) What is the frequency of the tuning fork? The speed of sound in air is 345 m/s. Answer in units of Hz.b) What is the value of L for the second resonant position? Answer in units of cm.c)What is the value of L for the third resonant position? Answer in units of cm.

Answers

Answer 1

Answer:

a. 3.45 kHz b. 5 cm c. 7.5 cm

Explanation:

a. What is the frequency of the tuning fork?

For a tube open at both ends, the frequency, f = nv/2L. The smallest frequency at the smallest length of air column, L = 5 cm = 0.05 m is the fundamental frequency and there, n = 1 and v = speed of sound in air = 345 m/s.

So, f = v/2L

So, f = 345 m/s/(2 × 0.05 m)

= 345 m/s ÷ 0.1 m

= 3450 Hz

= 3.45 kHz

b. What is the value of L for the second resonant position?

The second resonant frequency is f' = 2f

= 2 × 3450 Hz

= 6900 Hz

Since f = nv/2L and f' = second resonant frequency when n = 2.

So, f' = 2v/2L

f' = v/L

L = v/f'

= 345 m/s ÷ 6900 Hz

= 0.05 m

= 5 cm

c. What is the value of L for the third resonant position?

The third resonant frequency is f" = 3f

= 3 × 3450 Hz

= 10350 Hz

Since f = nv/2L and f" = third resonant frequency when n = 3.

So, f" = 3v/2L

2f' = 3v/L

L = 3v/2f'

= 3 × 345 m/s ÷ (2 × 6900 Hz)

= 1035 m/s ÷ 13800 Hz

= 0.075 m

= 7.5 cm

Answer 2

a)The frequency of the tuning fork will be 3.45 kHz.

b) The value of L for the second resonant position will be 5 cm.

c) The value of L for the third resonant position will be 7.5 cm.

What is frequency?

Frequency is defined as the number of repetitions of a wave occurring waves in 1 second.

The tuning fork's frequency for a tube with both ends open is;

f = nv/2L

f = 345 m/s/(2 × 0.05 m)

f= (345 m/s) / (0.1 m)

f= 3450 Hz

f= 3.45 kHz

f' = 2f is the second resonant frequency.

f'= 2 × 3450 Hz

f'= 6900 Hz

f = nv/2L

For n=2,

f' = 2v/2L

f' = v/L

The value of L for the second resonant position;

L = v/f'

L= 345 m/s ÷ 6900 Hz

L= 0.05 m

L= 5 cm

f' = 3f is the third resonant frequency.

f' = 3 × 3450 Hz

f'= 10350 Hz

f = nv/2L

For, n = 3.

f' = 3v/2L

2f' = 3v/L

The value of L for the third resonant position;

L = 3v/2f'

L=( 3 × 345 m/s)/(2 × 6900 Hz)

L= 1035 m/s / 13800 Hz

L= 0.075 m

L= 7.5 cm

Hence,The frequency of the tuning fork,value of L for the second resonant position and value of L for the third resonant position will be 3.45 kHz. 5 cm and 7.5 cm respectively.

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Related Questions

Which of the following statements is true? Decreasing the force acting on an object will increase its acceleration. Decreasing the mass of an object will decrease its acceleration. Increasing the force acting on an object will increase its acceleration. Increasing the mass of an object will increase its acceleration.

Answers

Answer:

Increasing the force acting on an object will increase its acceleration

Explanation:

The force acting on an object is given by the formula as follows :

F = ma

Where

m is mass and a is acceleration of the object

It can be seen that the force and the acceleration are directly proportional to each other.

It means if we increase the acceleration of the object, the force will increase and vice versa.

Hence, the correct option is (c) "Increasing the force acting on an object will increase its acceleration".

Answer:

i think Increasing the force acting on an object will increase its acceleration

Explanation:

Consider an open pipe of length L. What are the wavelengths of the three lowest tones produced by this pipe? Consider an open pipe of length L. What are the wavelengths of the three lowest tones produced by this pipe?

A. 3L, L, L/3

B. 2L, L, L/2

C. 2L, L, L/2

D. 4L, 2L, L 2L, L, 2L/3

Answers

Answer:

Explanation:

open pipe :

In open pipe , wavelength of tone produced =  2L / n where n is integer .

3 lowest tone or highest wavelength  = 2L / 1 , 2L / 2 , 2L / 3

= 2L , L , 2L/3

Closed pipe :

In closed pipe , wavelength of tone produced =  4L / n where n is odd integer

3 lowest tone or highest wavelength  = 4L / 1 , 4L / 3 , 4L / 5

= 4L  , 4L / 3 , 4L / 5

HELP ASAP!
on the screenshot.

Answers

6-A
7-B
8-A
Hope this helps

A father fashions a swing for his children out of a long rope that he fastens to the limb of a tall tree. As one of the children swings from this rope that is 6.00 m long, his tangential speed at the bottom of the swing is 9.50 m/s. What is the centripetal acceleration, in m/s2, of the child at the bottom of the swing

Answers

Answer:

The centripetal acceleration of the child at the bottom of the swing is 15.04 m/s².

                     

Explanation:

The centripetal acceleration is given by:

[tex] a_{c} = \frac{v^{2}}{r} [/tex]

Where:

[tex] v^{2}[/tex]: is the tangential speed = 9.50 m/s

r: is the distance = 6.00 m

Hence, the centripetal acceleration is:

[tex] a_{c} = \frac{v^{2}}{r} = \frac{(9.50 m/s)^{2}}{6.00 m} = 15.04 m/s^{2} [/tex]

Therefore, the centripetal acceleration of the child at the bottom of the swing is 15.04 m/s².

I hope it helps you!

Answer:

10.8n

Explanation:

For this case the centripetal force is given by:

Where,

m: mass of the object

v: tangential speed

r: rope radius

Substituting values in the equation we have:

Then, doing the corresponding calculations:

Answer:

The centripetal force exerted on the rope is:

What is the mass of a baseball thrown at 25 m/s resulting in a momentum
of 10 kg*m/s?
0.4 kg
2.5 kg
10 kg
250 kg

Answers

250kg

                                        would have momentum that is being caried by the impact of the trow                                                                                                                    

• 0.4kg
• 2.5kg
•10kg
•250kg

Please help

Answers

p=mv
m=p/v
m=10/25
=0.4 kg

In a fusion reactor, the high temperature of the order of 10 8 K is required in order that what condition is met

Answers

Answer:

High temperature of 108 million K

Explanation:

For the fusion reactor to be able to work optimally, then one of the most important conditions is the necessity of a very high temperature of about 108 million Kelvin. This is quite large, and is about six times hotter than the temperature existing at the core of the sun. At this temperature, the hydrogen state of the element is not a gas, but rather it is a plasma. Here, the atoms will be stripped of their electrons and are allowed to move freely. This condition is akin to the perfect condition for the reactor to function. It makes the hydrogen atoms gather enough energy for the reaction that takes place in the subsequent phases of this process.

If an object exerts a pressure of 12lb/in2 and it has an area of 0.2 in2 squared what is the weight of the object? Hint: weight is a force.

Answers

Answer:

Explanation:

As we know that ,

P=F/A

Where P=12 lb/in²  and A= 0.2 in²

Putt in formula to get F ( weight of body)

F=12*0.2

F=2.4 Ib

A bus has a speed of 1.3 m/s and a mass of 12,000 kg. A baseball has a
speed of 44.7 m/s and a mass of 0.145 kg. What is the kinetic energy of the
bus?

Answers

Answer:

find it yourself too lazy for math but here's the step

Explanation:

it's the object mass multiplied by the velocity.

Which evidence best supports that a device is an electric motor?
A. Electricity flows when a coil of wire is rotated by a hand crank.
B. Electricity flows from a battery through a loop of wire which then causes a needle to move.
C. Electricity flows from a battery to loop of wire and then through a galvanometer back to the battery.
D. Electricity flows through a coil of wire that is rotating because a magnet is pushing on the coil of wire.

Answers

Answer:

C

Explanation:

Answer:

the answer to this question is D

Explanation:

hope its helps

have a great day

a high ____will have a short wavelength.​

Answers

Question:

A high ____will have a short wavelength

Answer:

That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength. Light waves have very, very short wavelengths

Explanation:

Hope it help

Explanation:

Wave Is The Answer

HighWave

The sun uses what energy to gases, which causes particles to speed up, spread out, and rise up mark as brainlest. ASP Pls

Answers

Answer:

Heat causes the molecules to move faster, (heat energy is converted to kinetic energy ) which means that the volume of a gas increases more than the volume of a solid or liquid.

Through nuclear fusion, the sun is constantly using up the hydrogen in its core: Every second, the sun fuses around 620 million metric tons of hydrogen into helium. At this stage in the sun's life, its core is about 74% hydrogen.

During her last physical exam before takeoff, an astronaut was told that her weight was within the acceptable range required for astronauts. After she was in space for two weeks, her weight was recorded again. Which is the best explanation for the astronaut's significant weight loss? A. As mass increases, weight decreases. B. There is less gravitational force affecting her in space. C. She lost body mass during the flight due to a decrease in metabolism. D. The amount of matter in a body decreases as the distance from Earth increases.

Answers

Answer:

The most likely answer is option C: She lost body mass during the flight due to a decrease in metabolism.

Explanation:

There are different theories regarding this. One of fact is that astronauts drink and eat considerably less than normal during the first day of flight (probably due to sickness before adaptation). It is thought that their bodies adapt to the changes in accelerations they suffer during the trip and in space.

Solve the problems. Show all work, be SI units for force for weight) .

1. Find the weight of a 2.5 kg bowling ball.​

Answers

Answer:

1. 75 N

2. 6.8351 N

3. 700 N

Explanation:

1. Determination of the weight of the bowling ball:

Mass (m) = 7.5 kg

Acceleration due to gravity (g) = 10 m/s²

Weight (W) =?

Weight = mass × acceleration due to gravity

W = m × g

W = 7.5 × 10

W = 75 N

2. Determination of the weight of the object.

Mass (m) = 683.51 g

Weight (W) =?

We'll begin by converting 683.51 g to kg. This can be obtained as follow:

1000 g = 1 Kg

Therefore,

683.51 g = 683.51 g × 1 Kg / 1000 g

683.51 g = 0.68351 Kg

Thus, 683.51 g is equivalent to 0.68351 Kg.

Finally, we shall determine the weight of the object as follow:

Mass (m) = 0.68351 Kg

Acceleration due to gravity (g) = 10 m/s²

Weight (W) =?

Weight = mass × acceleration due to gravity

W = m × g

W = 0.68351 × 10

W = 6.8351 N

3. Determination of the weight of the KHS student.

Mass (m) = 154 lb

Weight (W) =?

We'll begin by converting 154 lb to Kg. This can be obtained as follow:

2.2 lb = 1 Kg

Therefore,

154 lb = 154 lb × 1 Kg / 2.2 lb

154 lb = 70 kg

Thus, 154 lb is equivalent to 70 kg.

Finally, we shall determine the weight of the KHS student as follow:

Mass (m) = 70 Kg

Acceleration due to gravity (g) = 10 m/s²

Weight (W) =?

Weight = mass × acceleration due to gravity

W = m × g

W = 70 × 10

W = 700 N

Which motion is best explained as forces acting according to Newton's third law of motion?
O A. An athlete lifts a heavy object and lets gravity pull it down.
B. An apple rolls off a table and gravity accelerates it to the floor.
O c. A car accelerates forward while air resistance pushes the car backwards.
O D. A rocket pushes gases backward while the gases push the rocket forward.

Answers

D. A rocket pushes gases backward while the gases push the rocket forward

Newton’s third law: for every action there is and equal and opposite reaction

A tourist drops (from rest) a ping pong ball from the top of the tower, which has a height of 174 meters. Assuming no air resistance, how long does it take for the ping pong ball to hit the ground

Answers

Given :

A tourist drops (from rest) a ping pong ball from the top of the tower, which has a height of 174 meters.

To Find :

How long does it take for the ping pong ball to hit the ground ?

Solution :

We know, equation of motion of object doing free fall is :

[tex]s = ut + \dfrac{gt^2}{2}[/tex]           ....1)

Here, g = 9.8 m/s² ( acceleration due to gravity )

Also, u = 0 m/s ( its free fall )

Putting these values in equation 1), we get :

[tex]174 = 0 + \dfrac{9.8\times t^2}{2}\\\\t = \sqrt{\dfrac{174\times 2}{9.8} }\ s\\\\t = 5.96 \ s[/tex]

Therefore, ball will take 5.96 s to hit the ground.

Suppose one cylinder is bolted to a sturdy ceiling. How many 81 kg football players would need to hang from the lower cylinder to pull the two cylinders apart

Answers

This question is incomplete, the complete question is;

The two 60 cm in diameter cylinders in Figure 13.15, closed at one end, open at the other, are joined to form a single cylinder, then the air inside is removed.

a) How much force does the atmosphere exert on the flat end of each cylinder?

b) Suppose one cylinder is bolted to a sturdy ceiling. How many 81 kg football players would need to hang from the lower cylinder to pull the two cylinders apart ?

Answer:

a) the atmosphere exert a force of 2.9 × 10⁴ N on the flat end of each cylinder

b) 36 football players each of 81 kg are needed to pull the two cylinders apart.

Explanation:

Given that;

diameter of cylinder is 60 cm = 0.6 m

then radius r will be 0.6/2 = 0.3 m

a)

How much force does the atmosphere exert on the flat end of each cylinder;

we know that; F = PA

inside its the flats end that its in question; Area A = πr².

We Know that, Pressure P due to atmosphere is 1.013 × 10⁵ Pa

so, F = 1.013 × 10⁵ Pa × π( 0.3 )²

F = 1.013 × 10⁵ Pa × 0.09π

F =  28641.9 N ≈ 2.9 × 10⁴ N

Therefore, the atmosphere exert a force of 2.9 × 10⁴ N on the flat end of each cylinder.

b) number of players needed to pull the two cylinders apart.

given that; m = 81 kg and g is 9.8 m/s²

n = F / mg

we substitute

n = 28641.9 / (81 × 9.8)

n = 28641.9 / 793.8

n = 36.08 ≈ 36

Therefore, 36 football players each of 81 kg are needed to pull the two cylinders apart.

The graph below shows the composition of the air we breathe. Which of the following statements correctly classified the air we breathe?
A. The air we breathe is an element because it is made of pure substances
B. The air we breathe is a compound because it is made of different pure substances.
C. The air we breathe is a heterogeneous mixture because it had visibly different substances and phases.
D. The air we breathe is a homogeneous mixture because it has substances but the same appearance throughout.

Answers

Answer:

D. The air we breathe is a homogeneous mixture because it has substances but the same appearance throughout.

Explanation:

The air we breathe is a homogeneous mixture.

Air is a mixture of many gases. A homogeneous mixture is one whose constituents exists in one phase.

Air is a gas - gas mixtures.

A mixture has indefinite composition. They consist of two or more elements and or compounds in any proportion by mass.

Constituents retain their identities i.e. physical properties are retained.

A person is walking north on a sidewalk at about 3.30 mph. At the same time the wind is blowing from the north (toward the south) at about 2.70 mph. What relative wind speed will the person sense

Answers

Answer:

[tex]V_R=5.80mph(-\hat j )[/tex]

Explanation:

From the question we are told that

Speed of man [tex]V_m=3.30mph[/tex]

Speed of wind  [tex]V_w=-2.70mph[/tex]

Generally the Relative wind speed V_R is mathematically given directly as

   [tex]V_R=V_w-V_m[/tex]

   [tex]V_R=-2.7-3.30[/tex]

   [tex]V_R=-5.80mph[/tex]

Therefore the relative wind speed will the person sense

   [tex]V_R=5.80mph(-\hat j )[/tex]

4. A driver takes 3.5 s to react to a complex situation. How far does the vehicle travel before the driver initiates a physical response to the situation (i.e., putting his or her foot on the brake)

Answers

This question is incomplete, the complete question is;

A driver takes 3.5 s to react to a complex situation while driving at a speed of 60 mi/h.

How far does the vehicle travel before the driver initiates a physical response to the situation (i.e., putting his or her foot on the brake)

Answer:

the distance travelled by the vehicle, before the driver initiates a physical response is 308 ft

Explanation:    

Given that;

Reaction time t = 3.5 sec

Speed S = 60 mi/h

we convert mile to foot and hour to seconds

so

Speed S = 60 mi/h =  (60×5280)/(60×60) = 316800/3600 = 88 ft/sec

Now, The distance travelled by vehicle before the driver  initiates physical response is equal to Lag distance. i.e

Lag distance = V × t

we substitute

Lag distance = 88 ft/sec  3.5 sec

Lag distance = 308 ft

Therefore, the distance travelled by the vehicle, before the driver initiates a physical response is 308 ft

the study of physical world is called?

Answers

Answer:

Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, Earth science, and astronomy.

Which property of electromagnetic waves must go down as the frequency goes

up?

Answers

Answer:

Wavelength

Explanation:

Velocity of a wave is given by

[tex]v=f\lambda[/tex]

where

[tex]f[/tex] = Frequency of wave = [tex]f=\dfrac{v}{\lambda}[/tex]

[tex]\lambda[/tex] = Wavelength of wave

We have the relation

[tex]f\propto \dfrac{1}{\lambda}[/tex]

Now, velocity of the wave in a given medium remains constant. So, if the frequency increases the wavelength must decrease in order to keep the velocity of the wave constant. Also if the frequency decreases the the wavelength increases.

A man runs 300 m West in 60 seconds. He then runs 100 m
North-west in 20 seconds.
What is his average velocity in metres per second?​

Answers

Answer:

5 m/s

Explanation:

Total distance = 300 + 100 = 400m

Total time = 60 + 20 = 80s

Velocity = 400/80 = 5m/s

Average velocity of man is 5 meter per second.

To find the average speed of an object we divide the total distance travelled by the total time time taken by object.

Total distance travelled by man = 300 + 100 = 400 m

Total time taken by man = 60 + 20 = 80 seconds

Average velocity,[tex]=\frac{400}{80} =5m/s[/tex]

Thus, Average velocity of man is 5 meter per second.

Learn more:

https://brainly.com/question/23856383

A 800kg car produces a motive force of 10,000N.

As it accelerates from rest it experiences a frictional resistance of 2,000N.

What is the net force acting on the car?

Answers

Answer:

the net force on the car is 8,000 N.

Explanation:

Given;

mass of the car, m = 800 kg

motive force of the car, F = 10,000 N

frictional force experienced by the car, Fk = 2,000 N

The net force on the car is calculated as;

∑F = F - Fk

∑F = 10,000 - 2,000

∑F = 8,000 N

Therefore, the net force on the car is 8,000 N.

At which region of a state's geology would an earthquake be more likely?


Near a divergent boundary of two plates


At the site of geologic uplift where island chains from


At the site of a convergent boundary as plates move together


Around a transform boundary between two plates that slide past each other

Answers

transform boundary USJSJSSOAKAMAMXMXHDJEUSUS

Answer:

The Answer is D

Explanation:

Hope this helps!!!

a wye-connected load has a voltage of 480v applied to it. What is the voltage drop across each phase

Answers

Answer:

[tex]Y_A=277.128 \angle 30v[/tex]

[tex]Y_B=277.128 \angle (-150)v[/tex]

[tex]Y_C=277.128 \angle (90)v[/tex]

Explanation:

From the question we are told that

Voltage [tex]V_L_L =480v[/tex]

Generally in a case of Y_connection [tex]V_p_ h[/tex] is mathematical represented as

[tex]V_p_h=\frac{V_l_l}{\sqrt{3}} \angle (\phi-30)v[/tex]

Generally voltage drop across phase A

[tex]Y_A=\frac{408}{\sqrt{3}} \angle -(0-30)[/tex]

[tex]Y_A=277.128 \angle 30v[/tex]

Generally voltage drop across phase B

[tex]Y_B=277.128 \angle (-30-120)[/tex]

[tex]Y_B=277.128 \angle (-150)v[/tex]

Generally voltage drop across phase C

[tex]Y_C=277.128 \angle (-30+120)[/tex]

[tex]Y_C=277.128 \angle (90)v[/tex]

A 2.5x10-3 kg paint chip comes off a satellite orbiting Earth. The velocity of the paint chip is

7000 m/s. Which is the kinetic energy of the paint chip?

F 1750)

G 6125 )

H 12.250

24,500

(7 Points)

Answers

Answer:

G. 6125

Explanation:

Step one:

given data

mass m=  2.5x10-3 kg

velocity v= 7000 m/s

Required

The kinetic energy

Step two:

The expression for the kinetic energy is

KE= 1/2m v^2

KE= 1/2*2.5x10^-3*7000^2

KE= 0.5*2.5x10^-3*7000^2

KE= 0.5*2.5x10^-3*49000000

KE= 0.5*122500

KE=6125J

Olympian Michael Johnson ran the 200 m dash in 19.32 seconds. What was his velocity?

Answers

Answer : 10.35 m/s





Explanation

NEED HELP ASAP!!!!!

A car speeds up from 15 m/s to 30 m/s in 12 seconds. What is the acceleration of the car?
A. 1.25 m/s2
B. 0.8 m/s2
C. 1.50 m/s2
D. 1.75 m/s2

Answers

Answer:

A, 1.25m/s^2

Explanation:

use formula v=v0+at to solve for a

a= v-v0/t

Plug in givens

30-15/12 to get 15/12 = 1.25m/s^2

A
copper wire of radius 2.4mm is fixed to a ceiling. When a load of 100 kg
is suspended at its lower end, it is extended by 1.5 mm. If the Young's
modulus of copper is 1.2 x 1011Nm?, calculate the length of the wire.​

Answers

The answer is 25.37 hope this helps
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