If the loudness drops to 90 % of its original value in 5.0 s , what is the time constant of the damped oscillation

Answers

Answer 1

This question is incomplete, the complete question is;

A gong makes a loud noise when struck. The noise gradually gets less and less loud until it fades below the sensitivity of the human ear. The simplest model of how the gong produces the sound we hear treats the gong as a damped harmonic oscillator. The tone we hear is related to the frequency f of the oscillation, and its loudness is proportional to the energy of the oscillation.

If the loudness drops to 90 % of its original value in 5.0 s , what is the time constant of the damped oscillation

Answer: the time constant of the damped oscillation is 47.44s

Explanation:

Given that;

t = 5.0s

Lets say Ao is the amplitude of initial loudness and later A(t) = 0.9 Ao

EXPRESSION for amplitude is  A(t) = Ao e^-t / T

t is time while T is time constant

so

0.9Ao = Ao e^-t / T  

0.9 = e^ -t/T

So we take the natural log of both the sides

ln (0.9) = -t/T

-0.1054 =  -t/T

0.1054 =  t/T

WE now substitute our value of t

0.1054 =  t/T

0.1054T =  5.0

T = 5 / 0.1054

T = 47.44s

therefore the time constant of the damped oscillation is 47.44s


Related Questions


A student creates an electromagnetic wave and then reverses the direction of the current. Which of the following will happen to the magnetic field?

Answers

Answer:

I believe the electromagnetic field should be reversed.

Explanation:

When a student creates an electromagnetic wave and then reverses the direction of the current, the direction of the magnetic field will be reversed.

What is an Electromagnetic wave?

An electromagnetic wave may be defined as a type of wave that is significantly created as a result of vibrations between an electric field and a magnetic field. These waves are composed of oscillating magnetic and electric fields.

According to the context of this question, when an individual is constructing an electromagnetic wave and then reverses the direction of the current, it will eventually affect the direction of the magnetic field in the same direction with respect to the current. So, if the direction of the current is reversed, the direction of the magnetic field would also be reversed.

Therefore, when a student creates an electromagnetic wave and then reverses the direction of the current, the direction of the magnetic field will be reversed.

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Your question seems incomplete. The most probable complete question is as follows:

A student creates an electromagnetic wave and then reverses the direction of the current. Which of the following will happen to the magnetic field?

The direction of the magnetic field will be reversed. The magnetic field will expand.The magnetic field would be canceled out and disappear.The magnetic field will cause the voltage of the battery to be reduced.

Which best explains a difference between Einstein’s general theory of relativity and his special theory of relativity?


His general theory includes uniform and accelerated motion, but his special theory applies only to uniform motion.

His general theory includes uniform and accelerated motion, but his special theory applies only to accelerated motion.

His general theory applies only to accelerated motion, but his special theory includes uniform and accelerated motion.

His general theory applies only to uniform motion, but his special theory includes uniform and accelerated motion.

Answers

Answer:

His general theory includes uniform and accelerated motion, but his special theory applies only to uniform motion.

Explanation:

According to Einstein's 1915 general theory of relativity, the force of gravity arises from the curvature of space and time.

According to theory of special relativity:

1. The laws of physics are the same for all non-accelerating observers

2. The speed of light in a vacuum was independent of the motion of all observers.

His general theory includes uniform and accelerated motion, but his special theory applies only to uniform motion.

Answer:

for those who dont like to read

the answer is A.

hope i helped

Explanation:

A boy whirls a ball on a string in a horizontal circle of radius 1 m. How many revolutions per minute must the ball make if its acceleration towards the center of the circle is to have the same magnitude as the acceleration due to gravity

Answers

Answer:

Nearest, the revolutions per minute will be 29.

Explanation:

Given that,

Radius of circle = 1 m

Acceleration a =g

We know that,

Angular frequency is defined as,

[tex]\omega=2\pi n[/tex]

Where, n = number of revolutions in one second

We need to calculate the revolutions in one second

Using formula of centripetal acceleration

[tex]a=\omega^2r[/tex]

Put the value of a and ω

[tex]g=(2\pi n)^2r[/tex]

[tex]n=\sqrt{\dfrac{g}{r}}\times\dfrac{1}{2\pi}[/tex]

Put the value into the formula

[tex]n=\sqrt{\dfrac{9.8}{1}}\times\dfrac{1}{2\pi}[/tex]

[tex]n=0.49[/tex]

We need to calculate the revolutions per minute

Using value for the revolutions per minute

[tex]n=0.49\times60[/tex]

[tex]n=29.4[/tex]

Hence, Nearest, the revolutions per minute will be 29.

Which factor affects the amount of runoff that occurs in an area?

land use
the water table
the saturation zone
amount of nutrients in soil

Answers

Answer:

A. land use

Explanation:

Answer:

a

Explanation:

A bird is flying in a room with a velocity field of . Calculate the temperature change that the bird feels after 9 seconds of flight, as it flies through x

Answers

Complete Question

The complete question is shown on the first uploaded image

Answer:

The temperature change is [tex]\frac{dT}{dt} = 1.016 ^oC/m[/tex]

Explanation:

From the question we are told that

   The velocity field with which the bird is flying is  [tex]\vec V =  (u, v, w)= 0.6x + 0.2t - 1.4 \ m/s[/tex]

   The temperature of the room is  [tex]T(x, y, u) =  400 -0.4y -0.6z-0.2(5 - x)^2 \  ^o C[/tex]

    The time considered is  t =  10 \  seconds

    The  distance that the bird flew is  x  =  1 m

 Given that the bird is inside the room then the temperature of the room is equal to the temperature of the bird

Generally the change in the bird temperature with time is mathematically represented as

      [tex]\frac{dT}{dt} = -0.4 \frac{dy}{dt} -0.6\frac{dz}{dt} -0.2[2 *  (5-x)] [-\frac{dx}{dt} ][/tex]

Here the negative sign in [tex]\frac{dx}{dt}[/tex] is because of the negative sign that is attached to x in the equation

 So

       [tex]\frac{dT}{dt} = -0.4v_y  -0.6v_z -0.2[2 *  (5-x)][ -v_x][/tex]

From the given equation of velocity field

    [tex]v_x  =  0.6x[/tex]

    [tex]v_y  =  0.2t[/tex]

     [tex]v_z  =  -1.4 [/tex]

So

[tex]\frac{dT}{dt} = -0.4[0.2t]  -0.6[-1.4] -0.2[2 *  (5-x)][ -[0.6x]][/tex]    

substituting the given values of x and t

[tex]\frac{dT}{dt} = -0.4[0.2(10)]  -0.6[-1.4] -0.2[2 *  (5-1)][ -[0.61]][/tex]      

[tex]\frac{dT}{dt} = -0.8 +0.84 + 0.976[/tex]  

[tex]\frac{dT}{dt} = 1.016 ^oC/m[/tex]  

distance is constant and time increseas

Will Speed increase or decrease?

Answers

Answer:

The speed will be decrease

The speed will decrease

please help asap
You jog for 55 minutes and reach a park that is 4.8 km away. What was your speed?​

Answers

Answer: 59.8 or 299/5​- 55 x 4.8=264

Explanation:

Or if you wish to multiply it then the answer is above with the addition version.

Hope this helped :)

Luck walked to a store that is 250m away and it took him 50secs while Layne walked to the mall that is 1000m away and took her 200s to do. What do they have in common?

A. Average speed
B. Acceleration
C. Displacement
D.mass

Answers

Answer:

Average speed

Explanation:

250/50=5

1000/20=5

A crane uses a single cable to lower a steel girder into place. The girder moves with constant speed. The cable tension does work WT and gravity does work WG. Which statement is true

Answers

Explanation:

Work done by a force is given by :

[tex]W=Fd\cos\theta[/tex]

Where

F is force, d is displacement and [tex]\theta[/tex] is the angle between F and d.

In this problem, a crane is moving in downward direction, the force gravity is in downward direction and the tension is in upward direction.

We know that if force and displacement is in same direction, work is positive while if force and displacement is in oposite direction, work is negative.

I would mean that, [tex]W_g[/tex] is positive, because gravity is parallel to the displacement and [tex]W_t[/tex] is negative, because the tension is opposite to the displacement.

How do I proton and and electron compared

Answers

What’s the question?

7N
6
→ 2N
Net Force:
Determine the net force acting on the object.

Answers

Answer:

When a force is applied to the body, not only is the applied force acting, there are many other forces like gravitational force Fg, frictional force Ff and the normal force that balances the other force. Therefore, the net force formula is given by, FNet = Fa + Fg + Ff + FN.

Explanation:

A vector of components (−23, −22) is multiplied by the scalar value of −6. What is the magnitude and direction of the resultant vector?

Answers

Answer:

(1,)

Explanation:

Answer:

magnitude: 21.6; direction: 33.7°

Explanation:

Find the linear velocity of a point moving with uniform circular motion, if the point covers a distance s in the given amount of time t. s

Answers

Answer:

The linear velocity is represented by the following expression: [tex]v = \frac{s}{t}[/tex]

Explanation:

From Rotation Physics we know that linear velocity of a point moving with uniform circular motion is:

[tex]v = r\cdot \omega[/tex] (Eq. 1)

Where:

[tex]r[/tex] - Radius of rotation of the particle, measured in meters.

[tex]\omega[/tex] - Angular velocity, measured in radians per second.

[tex]v[/tex] - Linear velocity of the point, measured in meters per second.

But we know that angular velocity is also equal to:

[tex]\omega = \frac{\theta}{t}[/tex] (Eq. 2)

Where:

[tex]\theta[/tex] - Angular displacement, measured in radians.

[tex]t[/tex] - Time, measured in seconds.

By applying (Eq. 2) in (Eq. 1) we get that:

[tex]v = \frac{r\cdot \theta}{t}[/tex] (Eq. 3)

From Geometry we must remember that circular arc ([tex]s[/tex]), measured in meters, is represented by:

[tex]s = r\cdot \theta[/tex]

[tex]v = \frac{s}{t}[/tex]

The linear velocity is represented by the following expression: [tex]v = \frac{s}{t}[/tex]

Help me Please!!!!!!!

Answers

The speed is equal to the area under the line up to the point where t .=15 s.
Do find the area of the triangle and that if the rectangle and add them together.
The area of the triangle is 25 and the rectangle is also 25 so the speed is 50 m/s

1. What quantity of heat is required to raise?

the temperature of 450 grams of water
from 35°C to 85°C?

capacity of water is 4.18 J/g °C.

Answers

Answer: Calculate the energy required in joules to raise the temperature of 450 grams of water from 15°C to 85°C? (The specific heat capacity of water is 4.18 J/g/°C)

Explanation:

The quantity of heat is required to raise the temperature of of water is 94050 joule.

What is law of conservation of energy?

Energy cannot be created or destroyed, according to the law of conservation of energy. However, it is capable of change from one form to another. An isolated system's total energy is constant regardless of the types of energy present.

The law of energy conservation is adhered to by all energy forms. The law of conservation of energy essentially says that the total energy of the system is conserved in a closed system, also known as an isolated system.

Mass of water: m = 450 grams

Initial temperature of water = 35° C

Final temperature of water = 85° C

Capacity of water is 4.18 J/g °C.

Hence, the  quantity of heat is required to raise = mass × Capacity  × raise in temperature

= 450 × 4.18 × (85 - 35) joule

= 94050 joule.

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what phase changes take place when you are adding energy to the substance

Answers

Answer:

During a phase change, a substance undergoes transition to a higher energy state when heat is added, or to a lower energy state when heat is removed. Heat is added to a substance during melting and vaporization. Latent heat is released by a substance during condensation and freezing. Explanation:

Name the part of the human eye which acts as a protective layer for the eye​

Answers

Answer:

Cornea

Explanation:

Cornea protects outer layer of the eye.

Victor has 100 trading cards, each with a distinct power level between 101 and 200 inclusive. Whenever he heads out, he always randomly selects 21 cards to bring with him just in case he meets a fellow collector. Prove that no matter which 21 cards he brings, Victor will always be able to select 4 of those cards that exhibit the following property:
Let the average power level of all 4 cards bep. The cards can be split into two pairs, each of which also has an average power level of p.

Answers

Answer:

Victor will always be able to select 4 of those cards with the following property

Explanation:

Number of trading cards = 100

victor selects 21 cards

let the 4 cards be labelled : A,B,C and D

The average power level of : A,B,C,D = ( A + B + C + D )/ 4 = P

let the two pairs be : ( A + B ) and ( C + D )

note: average power of each pair = P  and this shows that

( A + B ) = ( C + D ) for Victor to select 4 cards out of the 21 cards that exhibit the same property

we have to check out the possible choices of two cards out of 21 cards yield distinct sums.

= C(21,2)=(21x20)/2 = 210.

from the question the number of distinct sums that can be created using 101  through 200 is < 210 .

hence it is impossible to get 210 distinct sums therefore Victor will always be able to select 4 of those cards

A person following a liberal ideology would likely approve of

Answers

i’m
not sure sorry :5

A student uses a microwave oven to heat a meal. The wavelength of the radiation is 8.97 cm. What is the energy of one photon of this microwave radiation? Multiply the answer you get by 1025 to be able to input a number more easily into canvas. Enter to 2 decimal places.

Answers

Answer:

The energy of one photon is 2.21x10⁻²⁴ J. Multiplied by 10²⁵ is 22.10 J.

         

Explanation:  

The energy (E) of a photon is:

[tex] E = h\frac{c}{\lambda} [/tex]

Where:

h: is the Planck's constant = 6.62x10⁻³⁴ J.s

λ: is the wavelength of the radiation = 8.97 cm

c: is the speed of light = 3.00x10⁸ m/s

[tex] E = h\frac{c}{\lambda} = 6.62 \cdot 10^{-34} J.s\frac{3.00\cdot 10^{8} m/s}{8.97 \cdot 10^{-2} m} = 2.21 \cdot 10^{-24} J [/tex]

Hence, the energy of one photon is 2.21x10⁻²⁴ J.

Now, if we multiply the answer by 10²⁵ we have:

[tex] E = 2.21 \cdot 10^{-24} J \cdot 10^{25} = 22.10 J [/tex]

I hope it helps you!

The energy of one photon is 2.21x10⁻²⁴ J. Multiplied by 10²⁵ is 22.10 J.

Calculation of energy:

We know that

[tex]E = h\frac{c}{\lambda}[/tex]

Here

h be the Planck's constant = 6.62x10⁻³⁴ J.s

λ be the wavelength of the radiation = 8.97 cm

c be the speed of light = 3.00x10⁸ m/s

Now

Here we need to multiply the answer 10^25 so that the correct answer could come.

[tex]E = 6.62.10^{-34} \frac{3.00.10^{8}}{8.97.10^{-2}}[/tex]

=  2.21x10⁻²⁴ J.

= 22.10 J.

Hence, the energy of one photon is 2.21x10⁻²⁴ J. Multiplied by 10²⁵ is 22.10 J.

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What is the speaker’s power output if the sound intensity level is 102 dBdB at a distance of 25 mm ? Express your answer to two significant figures and include the appropriate units.

Answers

Answer:

Power  = 124.50 W

Explanation:

Given that:

The Sound intensity of a speaker output is 102 dB

and the distance r = 25 m

For the intensity of sound,

[tex]\beta (dB)= 10 \ log_{10 } (\dfrac{I}{I_o})[/tex]

where;

the threshold of hearing   [tex]I_o = 10^{-12} (W/m^2)[/tex]

[tex]\dfrac{102 }{10}= log_{10}( \dfrac{I}{10^{-12}})[/tex]

[tex]10^{10.2} = \dfrac{I}{10^{-12}}[/tex]

[tex]I = 10^{10.2} \times 10^{-12}[/tex]

I = 0.01585 W/m²

If we recall, we know remember that ;

Power = Intensity × A rea

Power = 0.01585 W/m² × 4 × 3.142 × (25 m)²

Power  = 124.50 W

A cannonball is fired horizontally from a 10 m high cliff at 20 m/s. How long will the cannonball be in the air? How far away will the cannonball strike the ground?

Answers

Answe ¡Buenos días! –

#3 ¡Buenas tardes! –

#4 ¡Bienvenid

Six seconds after starting from rest, a car is moving at 15 m/s. What is the car's
average acceleration?
6 m/s2
0-5 m/s?
5 m/s2
2.5 m/s?
-2.5 m/s?

Answers

Answer:

  2.5 m/s²

Explanation:

a = ∆v/∆t = (15 m/s)/(6 s) = (15/6) m/s² = 2.5 m/s²

It takes 3.8 x 10^-5 for a pulse of the radio waves from a radar to reach a plane and bounce back. How far is the plane from the radar?

Answers

Answer: 11400 m

Explanation:

Given:

t = 3.8 x 10^-5 s

v = 3 x 10^8 m/s

d = ?

Formula:

d = vt

  = (3.8 x 10^-5 s)(3 x 10^8 m/s)

  = 11400 m

hope this helps :)

The uniform movement allows to find the results for the distance from the radar to the plane is: 5.7 10³ m or 5.7 km

Kinematics studies the motion of objects looking for relationships between position, velocity and acceleration, in the special case that the acceleration is zero is called uniform motion and is described by the expression

                [tex]v = \frac{d}{t}[/tex]

                d = v t

Where v is the velocity, d the displacement and t the time.

Radar waves are electromagnetic waves with constant velocity

            v = 3 10⁸ m/s

They indicate that the time of the waves to go to the plane and return is 3.8 10⁻⁵ s, therefore if the speed is constant, the time to reach the plane is half of the total time.

          t = [tex]\frac{t_{total} }{ 2}[/tex]

          t = [tex]\frac{3.8 \ 10^{-5}}{2}[/tex]  

          t = 1.9 10⁻⁵ s

Let's calculate

        d = 3 10⁸ 1.9 10⁻⁵

        d = 5.7 10³

In conclusion with the uniform movement we can find the results for the distance from the radar to the plane is: 5.7 10³ m or 5.7 km

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A block of mass 20 kg is being pulled by a force F on a rough horizontal surface. If the
coefficient of friction is 0.4, calculate
a) the normal force, N
b) the static frictional force, f
c) the minimum force required for the block to move with uniform speed​

Answers

The normal force counteracts any vertical force acting on the system and is perpendicular to the surface. So find the weight of the block and add the two forces.

N - W = 0 because we aren’t accelerating in y direction.
W = mg = 20*9.8 = 196 Newtons
N -196 = 0
N = 196

The definition for frictional force is the normal force multiplied by the coefficient. Very simple formula.
N * us = Fs
196*0.4 = 78.4 Newtons

You kind of already found the minimum force. You would need to apply a force larger than 78.4
F - 78.4 = 0 because we are moving at a constant uniform speed
F = 78.4

How many turns are in its secondary coil, if its input voltage is 120 V and the primary coil has 210 turns

Answers

Complete Question

How many turns are in its secondary coil, if its input voltage is 120 V and the primary coil has 210 turns.

The output from the secondary coil is  12 V

Answer:

The value  is  [tex]N_s  =  21 \  turns [/tex]

Explanation:

From the equation we are told that

   The input voltage is  [tex]V_{in}  = 120 \ V[/tex]

   The number of turns of the primary coil is [tex]N_p =  210 \  turn[/tex]

    The output from the secondary is [tex]V_o =  12V[/tex]

From the transformer equation

   [tex]\frac{N_p}{V_{in}}  =\frac{N_s}{V_o}[/tex]

Here [tex]N_s[/tex] is the number of turns in the secondary coil

=> [tex]N_s  =  \frac{N_p}{V_{in}}  *  V_s[/tex]

=>[tex]N_s  =  \frac{210}{120}  *  12[/tex]

=>[tex]N_s  =  21 \  turns [/tex]

What is the volume of an object if it has a mass of 10 grams and a density of 87 g/ml

Answers

Answer:

The answer is 0.115 mL

Explanation:

The volume of a substance when given the density and mass can be found by using the formula

[tex]volume = \frac{mass}{density} \\[/tex]

From the question

mass = 10 g

density = 87 g/ml

We have

[tex]volume = \frac{10}{87} \\ = 0.114942528...[/tex]

We have the final answer as

0.115 mL

Hope this helps you



Explain why the bottom of the ship is deeper below the surface of the sea
when the ship is fully loaded with cargo

Answers

Answer:

uhh more mass = more pull by gravity = ship go sinky more

Explanation:

At a certain instant, a proton is moving in the positive x direction through a magnetic field in the negative z direction. What is the direction of the magnetic force exerted on the proton

Answers

Answer: positive y direction

Explanation:

we know that direction of velocity is in +x direction

now the magnetic force is in negative z direction

therefore the magnetic force , F = q × ( v × B)

F = ( i × [ - k ] ) direction

F = j direction

so the direction of the magnetic force on the proton is positive y direction.

Man A (70kg) and Man B (90kg) are hanging motionless from a platform at rest. What is the tension TA in the top rope if the platform accelerates upward at a constant rate of 2 m/s2

Answers

Answer:

The tension in the upper rope (top rope), T1 = 1,888 N

Explanation:

The Parameters that were given:

Mass A, M1 = 70kg

Mass B. M2 = 90kg

acceleration, a = 2 m/s2

Assume the rope doesn't have mass, acceleration due to gravity, g

= 9.8 m/s2

The tension, T in a platform = m (a + g)

Then the tension, T1 in the upper rope = m1 (a + g) + T2

Where T2 = Tension in the lower rope

First, we calculate T2

Since the platform accelerates upward the acceleration would be positive

T2 =  m2 (a + g)

T2 = 90kg ( 2 m/s2 + 9.8 m/s2)

T2 = 1,062N

To calculate the tension T1,

T1 = m1 (a + g) + T2

= 70kg (2 m/s2 + 9.8 m/s2) + 1062N

T1 = 1,888 N

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