as an automobile approaches an observer at rest, the driver sounds her 450 hz horn. if the car moves at 45 mi/hr, find the frequency heard by the stationary observer.

The Mass of the Brown dwarf's star,M₂ = 4.132 * 10²⁷ kg

Let M₁ be the mass of the main-sequence star

M₂ be the Mass of the brown dwarf

v₁ be the speed of the main-sequence star

v₂ be the speed of the brown dwarf

The system's typical separation is 1 AU, where r₁ = r₂

The brown dwarf's orbital speed is 22 times that of the main-sequence star.

Therefore, v₂ = 22 v₁

As a main sequence star, the sun

The Mass of the main-sequence star is 2 * 10³⁰ kg

Centripetal force, F = Mv²/r

M₁v₁²/r₁² = M₂v₂²/r²

M₁v₁² = M₂v₂²

M₂/M₁ = v₁²/v₂²

M₂/M₁ = (1/22)²

M₂/M₁ = 0.002066

M₂ = 0.002066M₁

M₂ = 0.002066 * 2 * 10³⁰

M₂ = 4.132 * 10²⁷ kg

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Answer:

The wave phenomenon that you are describing is known as the Doppler effect. The Doppler effect occurs when a wave, such as a sound wave, passes by an observer and the pitch of the wave seems to change. This is because the frequency of the wave changes as it moves closer to or farther away from the observer. The pitch of a sound wave is directly related to its frequency, so when the frequency of the wave changes, the pitch will also change. This effect is commonly observed with sound waves, but it can also occur with other types of waves, such as light waves.

Speed of light, is generally 299,792,458 m/s. The appropriate choice is "186,283 kilometers per second.

The speed of light is approx. 299,792,458 m/s. This is equal to approximately 186,282.397 miles per second or approximately 300,000 kilometers per second.

Therefore, the correct answer is "186,283 kilometers per second" or "300,000 km/sec". The other choices are incorrect because they are not the correct units for the speed of light. Visible light is an example of electromagnetic radiation that moves at the speed of light. Light and other electromagnetic waves appear to move instantly for many practical uses, but their finite speed has dramatic implications for vast distances and particularly sensitive measurements. The starlight that can be seen from Earth has been out there for a very long time, allowing people to view far-off objects and learn about the evolution of the universe. It can take minutes to hours for signals to reach from Earth to a spacecraft when corresponding with far-off space missions. The absolute shortest communication delay between computers, to computer memory, and within a CPU is fixed in computing at the speed of light.

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A cylindrical component known as a piston oscillates in the cylinder head (cylindrical chamber) of a locomotive's engine. 0.76 meters is the stroke, which is twice the amplitude. Its greatest speed is 7.2m/s.

We use v[tex]_{m}[/tex] =ωx[tex]_{m}[/tex]=2πfx[tex]_{m}[/tex], where the frequency is  180/(60s)=3.0Hz  and the amplitude is half the stroke, or x[tex]_{m}[/tex]=0.38m. Thus,

v[tex]_{m}[/tex]=2π(3.0Hz)(0.38m)=7.2m/s.

A piston is a disc or short cylinder that fits snugly inside an engine cylinder and imparts motion to a pump or a liquid or gas by moving up and down against it. Pneumatic and hydraulic cylinders, reciprocating engines, reciprocating pumps, gas compressors, and other related devices all have pistons. It is the moving part that has a cylinder around it and piston rings that seal the gas tightness.

To transfer force from the expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod is the function of a piston rod and/or connecting rod in an engine.

The processes of intake, compression, combustion, and exhaust are all four-stroke operations in automobile engines.

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The pipe must drop in height by 13.101 m in order to achieve this pressure.

Bernoulli stated that at whatever point along the fluid flow, the total amount of pressure, kinetic energy and potential energy per unit volume is the same.

P + 1/2 ρv² + ρ* g* h = constant

Given that, v = 1 m/s

P₁ = 101300 Pa

P₂ = 202600 Pa

ρ ethanol = 789 kg/m³

g = 9.8 m/s²

Now, let us write the bernoulli equation,

ρ*g*h₁ + P₁ = ρ*g*h₂ + P₂

P₁ - P₂ =  ρ*g*h₂ - ρ*g*h₁

( h₂ - h₁) = (P₁ - P₂)/ρ*g

Δh = (P₁ - P₂)/ρ*g

Δh = -101300 / ( 789 * 9.8) = -13.101 m

Minus sign indicates that height must be reduced.

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Answer:

Explanation:

The lower your center of gravity, the easier it is to keep your balance. If you're sitting on a chair, you can lean over more than if you're standing up. With your center of gravity low, you can lean further to one side or the other without creating enough turning force to tip you over.

Gamma rays, X-rays, ultraviolet radiation, visible light, infrared radiation, and radio waves are the components of the electromagnetic spectrum, listed in order of decreasing energy.

The parts of the electromagnetic spectrum are designated as follows, from highest to lowest energy: gamma rays, X-rays, ultraviolet radiation, visible light, infrared radiation, & radio waves. The radio wave region of the electromagnetic spectrum includes microwaves.

When wavelength is expressed in metres, 1/ stands for the number of waves that can be found in a wave train that is one metre long, or for the number of waves that can be found in a wave train that is one centimeter long. The wavenumber of the spectrum line is this number.

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An angle '[tex]\Theta[/tex]' on the circle Corresponds to an angle 2[tex]\Theta[/tex] on the part.

On the Mohr, the circle has a positive counterclockwise rotation, similar to the physical space convention for shear stress. is the clockwise shear stress and both are plotted. Mohr's circle is a graphical representation of the general state of stress at a point.

This is a graphical method for evaluating principal and maximum shear stresses. Normal and tangential stress in any plane. Soil mechanics use Mohr's circles to visualize the relationship between normal and shear stresses, and to estimate the maximum stress based on three or more soil samples taken from a site.

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Since a metal ball is considered a solid sphere So the electric field inside the metal ball is given by E = (p/3∈₀)r

Where r is the distance from the center and rho is charge density. Hence at the center r = 0

Then electric field

E = (p/3∈₀) x 0 = 0 N/C

Hence electric field at the center of the metal ball is due to its own charge only being 0N/C.

An electrical property is associated with any point in space when some form of electric charge is present. The magnitude and direction of the electric field are represented by the value of E and are called field strength or electric field strength or simply electric field.

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The rate per hundredweight is usually based on the shipment origin and destination, although the actual price charged for a particular shipment is normally subject to a minimum charge and may also be given a(n) surcharge.

A surcharge is any additional fee, tax, or charge that is tacked onto the cost of a good or service above and above the initial price that was provided. The advertised price of the commodity or service does not include a surcharge, which is frequently added to an already-applied tax. The cost of a surcharge can range and be either a set sum or a percentage of A governing body may apply this fee in order to raise additional funds or cover the expense of rising commodity prices. Consumers who purchase specific goods and services may be subject to surcharges, which are additional fees and/or taxes. At the moment of sale, they are included in the cost of the purchase. Thus, whenever you buy something,

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The tubes with lengths of 15, 45, and 75 cm are found to resonate with this wavelength. Additionally, resonance is seen for tubes with lengths of 25 and 75 cm and 31 and 93 cm.

For this reason, at the place where the tube is closed, we have a node, and at the open point, we have a belly; in this case, the fundamental wave is = 4L. To determine the length of the tube that has resonance, we must establish the natural frequencies of the tubes.

The following resonance, known as the first harmonic, is 3 = 4L / 3.

The next fifth harmonic resonance is 5 = 4L / 5, and we can see that its general form is n= 4L / n, where n = 1, 3, and 5.

Let's apply these terms to the issue at hand.

Start with the wavelength that is the shortest.

Lam equals 60 cm.

Let's determine the length of the tube this harmonica provides.

L = λ n / 4

n = 1 L = 60 will yield the shortest tube length. 1/4\s L = 15 cm

For n = 3 L = 60 3/4\s L = 45 cm

For n = 5 L = 60 5/4\s L = 75 cm

For n = 7 L = 60 7/4\s L = 105cm

We can see that the harmonics 1, 3 and 5 of the tubes with lengths 15, 45, and 75 resonate with this wavelength.

b) λ = 100 cm

For n = 1 L = 100 1/4\s L = 25 cm

For n = 3 L = 100 3/4\s L = 75 cm

For n = 5 L = 100 5/4\s L = 125 cm

There is resonance in the fundamental and third ammonium frequencies for lengths of 25 and 75 cm. L = 124 1/4 L = 31 cm

In the case of the second resonance, L = 124 3/4 L = 93 cm.

For tubes with lengths of 31 and 93 cm, resonance occurs in the fundamental and third harmonics.

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Each force produces a negative amount of effort (option d). Whenever there are two opposing forces, the net force will always be negative, no matter how strong one force is compared to the other. Reduced kinetic energy of the particle is indicated by a negative force.

When an object interacts with another object, it experiences a push or pull that is known as a force. Any instant two things connect, a force is transmitted to each one of them.

In daily life, forces can take many different forms. a bat's force on the ball is equal to its weight. the amount of pressure used by the hair brush to brush hair.

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The statement which is true regarding the motion of the satellite is D) The tangential velocity of the satellite does not remain constant.

Any object in orbit around the earth, the sun, or another large body is considered a satellite.

The satellite is able to maintain orbital motion even as gravity pulls it inward thanks to its tangential velocity. The necessary centripetal force is provided by gravitational attraction.

Newton was the first to say that a projectile launched with sufficient speed would actually orbit the earth.

The satellite moves faster when it is close to the earth and slows down while moving away to the top of the ellipse.

The question is incomplete. The complete question is ' A) The gravitational force exerted on the satellite by the moon will increase after time t0.

B) The satellite accelerates in a direction that is parallel to the direction of the tangential velocity.

C) The satellite will move toward the moon after time t0.

D) The tangential velocity of the satellite does not remain constant.'

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160 Hz is the higher harmonics of a string fixed at both ends that has a fundamental frequency of 80 Hz.

According to this option c) is correct answer.

A string's fundamental frequency, succeeding frequencies, and two ends are defined as the sum of the entire depending on the number of harmonics. In other words, higher harmonics specify the frequencies that follow under the functions 2f, 3f, 4f, 5f, etc.

As a result, the higher harmonics would be:

1 x 80 Hz Equals 80 Hz (1st harmonic and Fundamental Frequency)

2 × 80Hz Equals 160Hz (2nd harmonic) (2nd harmonic)

3 x 80Hz Equals 240Hz (3rd harmonic)

4 × 80Hz = 320Hz (4th harmonic)

5 x 80Hz Equals 400Hz (5th harmonic)

As a result, the two higher harmonics of a string with an 80Hz fundamental frequency are 160Hz and 240Hz.

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I understand that the question you are looking for is:

Select the higher harmonics of a string fixed at both ends that has a fundamental frequency of 80 Hz.

a)280 Hz

b) 400 Hz

c) 160 Hz

d) 200 Hz

e) 180 Hz

(a) The angular frequency is  2.7 Hz

(b) The maximum speed is  2.04 m/s

(c) The maximum value is occur at mean position

 so the dispalcement is zero

(d) The maximum acceleration is 34.68 m/s^2.

(e) The acceleartion should be maximum at extrem positions

  so the position  x = A = 12 cm

( f )  The force on the block  15.6 N

Calculation :

The mass of the block m = 0.45 kg

The dispalcement of the block

 x = 12cm cos [(17 rad/s) t + (π/2 rad)]

 (a) The angular frequency

                 ω = 17 rad/s

                  2πf = 17 rad/s

then the frequency

               f = 17 / 2π = 2.7 Hz

(b) The maximum speed

              v max = Aω  = (12 cm) (17 rad/s)

                                 = 2.04 m/s

(c) The maximum value is occur at mean position

 so the dispalcement is zero

(d) The maximum acceleration

     a max  = Aω^2

                = (0.12 m) (17)^2 = 34.68 m/s^2

(e) The acceleartion should be maximum at extrem positions

  so the position  x = A = 12 cm

(f)  The force on the block

           F = ma = (0.45 kg) (34.68 )

                        = 15.6 N

Force or Energy Exercised or Applied: Cause of Movement or Change: Active Force. force of nature

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4600 j work is done.

To find the amount of work done, the equation for work must be used. This equation is Work = Force x Distance. Force is equal to the mass of the box multiplied by the acceleration due to gravity, and the distance is 18 meters. The angle of 24 degrees above the horizontal must also be taken into account, therefore the cosine of 24 degrees must be used. The mass of the box is 64 kg and the acceleration due to gravity is 9.8 m/s2. After plugging in all the values, the work done is 4600 J.

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The velocity of the satellite as it passes point B in its orbit is vᵇ = v₀a/b

The angular momentum of a inflexible item is described as the made of the moment of inertia and the angular velocity. it's miles analogous to linear momentum and is challenge to the essential constraints of the conservation of angular momentum principle if there's no outside torque at the item.

The belongings of any rotating object given by using moment of inertia times angular velocity. it's miles the assets of a rotating frame given by way of the fabricated from the instant of inertia and the angular speed of the rotating object.

(a)  the total energy of the satellite when it is at A:-

     E = PE + KE = - G*Me*M/a + 1/2mv₀²

(b) the magnitude of the angular momentum of the satellite about the center of the Earth when it is at A:-

    L = mvr = mv₀a

(c) Conservation of angular momentum gives,  

    mv₀a =  mvᵇb, or vᵇ = v₀a/b

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The movement of the ball down the ramp can be shown by option B.

We know that the question has clearly said that the ramp was curved and this is going to help in shaping our discussion. In this case, it is clear that the the ball  rolls down a curved ramp as shown. The movement of the ball can be typified by the use of dotted lines.

In this case, we can see that the ball is going to continue to move in a curved path as the ball is moving down the ramp as has been shown in the image.

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The force applied on the body that is on the inclined plane is given as, F=mgsinθ, F=2×9.8×sin30  =9.8N and f=μmgcosθ f=0.7×2×9.8cos30 =11.88N.

Any increase in the moving force will result in slippage; limiting friction only exists when the moving force and the force opposing motion are equal.

The limiting frictional force is independent of the area of contact and proportional to the normal reaction between the contacting surfaces.

The amount of friction that can be produced when two static surfaces come into touch. A motion will start as soon as the force applied to the two surfaces surpasses the limiting friction. The normal response force and the coefficient of limiting friction are combined to get the limiting friction for two dry surfaces.

Therefore, The force applied on the body that is on the inclined plane is given as, F=mgsinθ, F=2×9.8×sin30  =9.8N and f=μmgcosθ f=0.7×2×9.8cos30 =11.88N.

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Mohr's circle can be used to calculate the stresses on an oblique section if the stress condition on two planes and the angle between those planes are known. The correct option to this question is C.

An illustration of the transformation equations for plane stress problems is Mohr's circle. The relationships between the normal and shear loads operating on a stress element at any desired orientation can be visualized using this technique.

A Mohr's circle must have a diameter, and in order to draw the diameter, two straight line endpoints' coordinates are needed. Apply the principles on Planes A1 and B1 to obtain the stress locations for Mohr's circle diameter if the shear axis is positive upwards.

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Complete question: Consider the following statements:

Mohr's Circle is used to determine the stress on an oblique section of a body subjected to

1. direct tensile stress on one plane accompanied by a shear stress.

2. direct tensile stresses in two mutually perpendicular directions accompanied by a simple shear stress.

3. direct tensile stress in two mutually perpendicular directions.

4. A simple shear stress

Select the correct answe using the codes given below:

A 1 and 4

B 2 and 3

C 1, 2, 3 and 4

D 1, 2 and 3



Answer:

i think its stress (c) hope this helpa

Answer:

C. the ability to withstand stress

Explanation:

The strength of a material refers to its ability to withstand stress. Stress is a measure of the force applied to a material, and it can be either tensile (stretching) or compressive (squeezing). A material's strength is typically measured by its ability to resist deformation or failure under a given amount of stress.

The position of the piston is 3.785 cm. The velocity of the piston is -2.585 cm/s. The acceleration of the piston is −15.14 cm/s The period of piston is 3.14 s and the amplitude of piston is 4 cm.

It is a kind of periodic motion bounded between two extreme points. For example, Oscillation of Simple Pendulum, Spring-Mass System. The object will keep on moving between two extreme points about a fixed point is called the mean position (or) equilibrium position along any path.

(a) The equation for the piston's position is given as

= x=(4.00 cm)cos(3t+6π )

At t=0,  

= x =(4.00 cm)cos(6π )

= x = 3.785 cm

(b) Differentiating the equation for position with respect to time gives us the piston's velocity:

= v = dt/dx = −(8.0 cm/s)sin(2t+ 6π )

At t=0,

= v = dt/dx = −(8.0 cm/s)sin(6π )

= v = -2.585 cm/s

(c) Differentiating again gives its acceleration:

= a = dv/ dt =−(16.0 cm/s 2 )cos(2t+ 6π )

At t=0,

= a = −(16.0 cm/s 2 )cos(6π )

= a = −15.14 cm/s

(d) The period of motion is = T

= T = ω/2π

= T = 2/2π

= T = 3.14 s

and,

The amplitude directly from the equation for x =

= A = 4 cm

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If the blade rotates with a constant angular velocity of 20 rad/s the work done on the blade by the motor in 1.0 min IS 960 J.

A torque is a force that causes rotation. Tells how effective force is at twisting or rotating an object.

Conditions for Equilibrium is that when FNet = 0 Translational EQ (Center of Mass) tNet = 0 Rotational EQ (True for any axis). Choose axis of rotation wisely to make problems easier, But as long as you’re consistent everything will be okay.

Gravitational Force Weight = mg, acts as force at center of mass, Torque about pivot due to gravity t = mgd, object not in static equilibrium.

As we know,

work = torque x angular displacement

θ = ωt

θ = 20 x 60

θ  = 1200rad

hence,

work = 0.80 x 1200

W = 960J

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'u' must the spaceship travel for the scientists to have enough time to complete their laboratory by the time half of the isotope has decayed at speed of  2.416*10⁸ m/s .

Calculation :

[tex]29 = \frac{16}{1-\frac{c}{v} ^{2} }[/tex]

v = 0.805 * C

V = 0.805 * 3*10*⁸

   = 2.146*10⁸ m/s

Isotopes are two or more types of atoms that have the same atomic number (number of protons in the nucleus) and position in the periodic table (and thus belong to the same chemical element), but that differ because of their nucleon number (mass number). The number of neutrons in the core is different. All isotopes of a particular element have approximately the same chemical properties, but they have different atomic masses and physical properties

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Angular speed when it is on the frictionless side of the track is 89.7 rad/s

Given that, mass, m=0.14 kg

Ball is released. from rest. at a height. of,  h= 0.83 m

Solid sphere of radius, R = 3.8 cm

                                       =0.038 m  

From the conservation of  energy

                          ΔK  = ΔU  

1/2 mv2 +   1/2 Iω2   = mgh

Here,  I=2/5MR2  ,  v=Rω

1/2 mv2 + 1/2 (2/5mR2)(v/R)2  =mgh

                          1/2 [v2 +2/5 v2] =gh

                           7/10 v2 = gh

                            0.7v2 = gh

                                  v =√ [gh / (0.7) ]

                                     =√ [(9.8 m/s2)(0.83 m) / (0.7) ]  

                                     = 3.408 m/s

Consequently, angular speed on the frictionless side of the rail,

                                  ω = v/R

                                     = (3.408 m/s)/(0.038 m)

                                     = 89.7 rad/s

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The correct answers are: a) The rod is negatively charged and d) The rod is positively charged.

When the sphere is brought near the upper end of the rod and the rod rotates clockwise, this indicates that the sphere has a positive charge.

When the sphere is brought to point X near the lower end of the rod and the rod rotates counterclockwise, this also indicates that the sphere has a positive charge.

The other two options are not correct. The rod is not uncharged, because it has a charge when the sphere is brought near it. The rod also does not have no net charge until the sphere is brought near it, because it has a charge when the sphere is brought near it.

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Yes, that's correct. The FCC (face-centered cubic) crystal structure is a common structure for many metals, including platinum. The lattice constant is a measure of the distance between the atomic planes in a crystal structure. It is equal to the distance between two adjacent atoms in the lattice and is typically measured in nanometers (nm). The lattice constant for platinum is approximately 0.39239 nm.

Platinum is a dense, ductile, and malleable metal with a high melting point and good electrical and thermal conductivity. It is resistant to corrosion and is often used in catalytic converters, jewelry, and electronic components. It is also used in the production of chemicals, pharmaceuticals, and other industrial applications.

The points of the design altitude for the rocket, when the stagnation pressure is of 400 psi, using given plots will be :-

The Exit velocity and Pressure in the case of a rocket motor are 1290m/s and 8.1 atm respectively. The C* and thrust propellant calculations are based on certain formulas.

Therefore, these are the points of the design altitude for the rocket, when the stagnation pressure is of 400 psi, using given plots.

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[NOTE: THIS IS AN INCOMPLETE QUESTION. THE COMPLETE QUESTION IS: Consider a rocket motor equipped with a nozzle in which the stagnation conditions are 3000 K and 60 atm. The specific heat ratio is 1.25 and the molecular weight of the propellant is 18. The nozzle throat diameter is 5 cm and the nozzle exit diameter is 30 cm. a. Calculate the exit velocity b. Calculate the exit pressure c. Calculate c* for this propellant d. Calculate the mass flow rate for the rocket e. If the rocket is fired at sea level, calculate the thrust. f. If the rocket is fired at sea level, calculate the thrust coefficient g. If the rocket is fired at sea level, calculate the effective exhaust velocity h. If the rocket is fired at sea level, calculate the specific impulse. i. If the rocket is fired in space, calculate the thrust. j. If the rocket is fired in space, calculate the thrust coefficient k. If the rocket is fired in space, calculate the effective exhaust velocity I. If the rocket is fired in space, calculate the specific impulse]

The magnitude of the electrostatic force exerted on the proton by the electron is greater than that exerted on the electron by the proton.

What kind of force is electrostatic?

The Coulomb's inverse-square law, sometimes known as Coulomb's law, is an observational physical principle that measures the force exerted between two electrically charged particles that are stationary. Common names for the electric created between two charged objects at rest include electrostatic force and Coulomb force.

Between two charges that are separated by a distance, there is an electrostatic force. The size of each charges and the separation between them determine the strength of the electrostatic force. Two charges that are either positive or negative when placed together repel one another.

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The waves are called periodic wave if waveform repeats in time interval T.              A wave is said to be periodic if its duration of transmission is infinity. In a periodic wave wavelength and frequency is regulated. In a given time interval the wave completes one cycle.

For a periodic wave the wave function is y(x,t) = A sin2(x -vt) .The term 2 scales the wave to the natural period of the sin function. The term A gives the amplitude of the wave which is the maximum displacement of the wave.

If the velocity of the wave remains constant, then as the frequency of the wave is increased, the wavelength decreases  

The phase difference  between any two points on a wave is found as follows:-At P1 the phase is 1 = kx1- t1 +,  

At P2 the phase is 2 = kx2- t2 +.

So the phase difference  is  = 2-1 = k(x2 - x1)- (t2 - t1)                                                                   The wave speed is given by:-          v=k=2f2/=f    

Examples of periodic wave can be seen in:-

1.Electromagnetic wave in optical fibre

2.Sound from a guitar string

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