What Is The Average Rate At Which This Wave Carries Energy Across Unit Area Per Unit Time?

7W/m2

What is the average power per unit area of the EM wave?

If an electromagnetic wave falls onto an area A where it is absorbed then the power delivered to that area is P = S∙A. The time average of the magnitude of the Poynting vector is called the irradiance or intensity. The irradiance is the average energy per unit area per unit time. = 2>/(μc) = Emax2/(2μc).

Is the energy transported per unit area and per unit time?

The energy per unit area per unit time passing through a plane perpendicular to the wave called the energy flux and denoted by S can be calculated by dividing the energy by the area A and the time interval Δ t . S = Energy passing area A in time Δ t A Δ t = u c = ε 0 c E 2 = 1 μ 0 E B .

What does Poynting vector represent?

In physics the Poynting vector represents the directional energy flux (the energy transfer per unit area per unit time) or power flow of an electromagnetic field. The SI unit of the Poynting vector is the watt per square metre (W/m2).

See also how does earth’s varying distance from the sun affect our seasons

What is the average rate at which this wave carries energy across unit area per unit time express your answer using three significant figures?

What is the average rate at which this wave carries energy across unit area per unit time? Solution: The average rate at which this wave carries energy across unit area per unit time is the average magnitude of the Poynting vector. −7W/m2.

What is the average energy transported over time per unit area by this electromagnetic wave?

The time average of the energy flux is the intensity I of the electromagnetic wave and is the power per unit area. It can be expressed by averaging the cosine function in Equation 16.4.

At what average rate does the wave transport energy?

At what average rate does the wave transport energy? The average rate of energy transport is the average power Pavg as given Eq. 16.36. v=√τμ=√45N0.525kg/m=9.26m/s.

What is the rate of energy flow of the wave?

The rate of energy flow per unit area of an electromagnetic wave has an average value of intensity as I=0.695 W/m2 I = 0.695 W / m 2 .

How much energy does a wave have?

Kinetic energy the energy of motion in waves is tremendous. An average 4-foot 10-second wave striking a coast puts out more than 35 000 horsepower per mile of coast. Waves get their energy from the wind.

What is time average Poynting vector?

6 Time-Averaged Poynting Vector. The instantaneous Poynting vector is defined as the cross-product E ¯ ˜ ( r ¯ t ) × H ¯ ˜ ( r ¯ t ) . When the fields are time-harmonic i.e. (2.30)

Which electromagnetic wave has highest wavelength?

Radio waves infrared rays visible light ultraviolet rays X-rays and gamma rays are all types of electromagnetic radiation. Radio waves have the longest wavelength and gamma rays have the shortest wavelength.

What is the average energy density U of the microwave radiation?

10-14 J/m3

The microwave radiation left over from the Big Bang explosion of the universe has an average energy density of 4.0 Ã— 10-14 J/m3.

How do you find the energy of a wave?

The energy in a wave is determined by two variables. One is amplitude which is the distance from the rest position of a wave to the top or bottom. Large amplitude waves contain more energy. The other is frequency which is the number of waves that pass by each second.

How does the intensity of or energy carried by a wave change with distance as the wave moves further away from the source of the wave?

As the wave moves out from a source the energy is conserved but the intensity decreases as the area increases.

What is energy transfer by electromagnetic waves?

Like other waves electromagnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation. Electromagnetic waves can transfer energy through matter or across empty space.

What is the energy carried by an electromagnetic wave?

The energy carried by any wave is proportional to its amplitude squared. For electromagnetic waves this means intensity can be expressed as Iave=cϵ0E202 I ave = c ϵ 0 E 0 2 2 where Iave is the average intensity in W/m2 and E is the maximum electric field strength of a continuous sinusoidal wave.

How does an electromagnetic wave carries energy from place to place?

In electromagnetic waves energy is transferred through vibrations of electric and magnetic fields. In sound waves energy is transferred through vibration of air particles or particles of a solid through which the sound travels. In water waves energy is transferred through the vibration of the water particles.

What are Travelling waves find the rate at which energy is transported by a wave Travelling along a string?

As a sinusoidal wave moves down a string the energy associated with one wavelength on the string is transported down the string at the propagation velocity v. From the basic wave relationship the distance traveled in one period is vT = λ so the energy is transported one wavelength per period of the oscillation.

How do you calculate wave speed?

Wave speed is the speed at which a wave travels. Wave speed is related to wavelength frequency and period by the equation wave speed = frequency x wavelength.

What happens to the average power of the wave amplitude is halved?

wave with frequency 120.0 Hz and amplitude 1.6 mm travels along the wire. (a) Calculate the average power carried by the wave. (b) What happens to the average power if the wave amplitude is halved? … (b) Since power is proportional to the square of amplitude halving the amplitude reduces power by a factor of 4.

What is the meaning of the average power of transverse wave?

Physics questions and answers. What is the meaning of the average power of transverse wave? a) It is the average rate at which energy (both kinetic and potential) is transmitted by the wave.

What is the average power transmitted down the string?

The time-averaged power of a sinusoidal wave on a string is found by Pave=12μA2ω2v P ave = 1 2 μ A 2 ω 2 v where μ is the linear mass density of the string A is the amplitude of the wave ω is the angular frequency of the wave and v is the speed of the wave.

How is energy transferred in transverse waves?

The particles involve vibrate around in compressions and rarefractions which would be perpendicular to the oscillation. Energy transfer is work done and work done is force x displacement. The particles get displaced while exerting a force hence energy is transferred.

How much energy is in a large wave?

Wave power formula

In major storms the largest waves offshore are about 15 meters high and have a period of about 15 seconds. According to the above formula such waves carry about 1.7 MW of power across each metre of wavefront. An effective wave power device captures as much as possible of the wave energy flux.

How do you calculate ocean wave energy?

The potential energy per unit area of a water surface raised by ς is given by Ep = ½ ρ g ς2. For a theoretical sinusoidal wave of amplitude H/2 averaged over a wave period this becomes Ep = 1/16 ρgH2 . Kinetic energy can be shown to have an equal value integrated over depth.

How much does ocean energy cost?

The World Renewable Energy Report estimates the cost of wave energy at an average of 9 cents/kWh and tidal and current an average of 8 cents/kWh. Recent EPRI reports have found that presently the cost of power from ocean technologies ranges from 7 cents to 16 cents/kw in a low case scenario.

What is a time average?

The Time Average algorithm calculates a time-weighted average of the values in a sample. Unlike the Average algorithm which simply divides the sum of the values in the sample by the number of values the Time Average algorithm takes into account the amount of time between value changes.

What is the magnitude of Poynting vector?

Applying the definition of cross product (see vector) and the knowledge that the electric and magnetic fields are perpendicular to each other gives the magnitude S of the Poynting vector as (1/μ)EB where E and B are respectively the magnitudes of the vectors E and B.

What do you mean by wave impedance?

The wave or radiation impedance of an electromagnetic wave is defined as the ratio of its electric to magnetic field intensities that is E/H. E is measured in volts per meter and H is measured in amperes per meter. … The wave impedance in free space is determined by the source of the radiation.

Which wave has highest energy?

Gamma rays
Gamma rays have the highest energies and shortest wavelengths on the electromagnetic spectrum.May 30 2019

Which wave has shortest wavelength?

Gamma Rays

Gamma Rays-have the smallest wavelengths and the most energy of any other wave in the electromagnetic spectrum.

What is the longest to shortest wavelength?

Order is as follows (shortest to longest wavelength): Gamma X-Rays UV Visible Infrared Microwaves Radio Waves.

How do you find energy density in physics?

Energy density can be written as uB=B22μ u B = B 2 2 μ .

Categories FAQ