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4 years ago

15

The maximum allowed leakage of microwave radiation from a microwave oven is 5.0 mw/cm2. if microwave radiation outside an oven h

as the maximum value, what is the amplitude of the oscillating electric field?

2 answers:

irina [24]4 years ago

8 0

Answer:

194 V/m

Explanation:

In order to find electric field, we can use the formula of power density

i.e Pd = E^2 / Z

where:

Pd = power density in W/m^2

E = electric field strength in V/m

Z = impedance of free space = 120 * π

E = sqrt(Pd * Z) -----> re-arranging it for E

before solving, convert Pd unit into W/m^2

Pd= 5mW/cm^2 = 50 W/m^2

Solving for E:

E= sqrt(50 * 120 * π)

E = 137.3 V/m

the above value is RMS value

In order to find the peak amplitude of the oscillating field will therefore be 137.3 * sqrt(2) = 194 V/m

klasskru [66]4 years ago

3 0

Answer:

E_peak = 194 N/C

Explanation:

Given:-

- The Power density Pd = 5.0 mW/cm^2

- The impedance of free space Z_o = 376.73 ohms

Find:-

If microwave radiation outside an oven has the maximum value, what is the amplitude of the oscillating electric field?

Solution:-

- The oscillating electric field strength E root mean squared can be determined by the Power Density formula applied for electromagnetic waves in free space. We have:

Pd = E^2_rms / Z_o

E_rms = sqrt ( Pd * Z_o )

- Solve for electric field strength E_rms:

E_rms = sqrt ( 50 * 376.73 )

E _rms= 137.24612 N / C

- The E obtained is the rms value. To obtained the peak value of E, we need to multiply the transformation factor √2.

E_peak = E_rms * √2

E_peak = 137.24612 * √2

E_peak = 194 N/C

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3 years ago

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Explanation:

Given that,

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(b). We need to calculate the kinetic energy of an electron

Using formula of kinetic energy

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$E=\dfrac{(6.63\times10^{-34})^2}{2\times9.1\times10^{-31}\times(6.0\times10^{-9})^2}$

$E=6.709\times10^{-21}\ J$

(c). We need to calculate the energy of photon

Using formula of energy

$E = \dfrac{hc}{\lambda}$

$E=\dfrac{6.63\times10^{-34}\times3\times10^{8}}{6.0\times10^{-15}}$

$E=3.315\times10^{-11}\ J$

(d). We need to calculate the kinetic energy of an electron

Using formula of kinetic energy

$\lambda=\dfrac{h}{\sqrt{2mE}}$

$E=\dfrac{h^2}{2m\lambda^2}$

Put the value into the formula

$E=\dfrac{(6.63\times10^{-34})^2}{2\times9.1\times10^{-31}\times(6.0\times10^{-15})^2}$

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Hence, This is the required solution.

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KATRIN_1 [288]

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A pickup truck is traveling down the highway at a steady speed of 30.1 m/s. The truck has a drag coefficient of 0.45 and a cross

Sav [38]

Answer:

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Explanation:

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Answer:

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b) up

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The complete question is

If the velocity of a proton is straight up(thumb pointing up) then RHR2 (right hand rule) shows that the force points to the left. What would the direction of the force be if the velocity were a)down, b)to the right, c)to the left, d)into the page, and e)out of the page?

The right hand rule for a positive charge states that...

Hold the thumb of the right hand at right angle to the rest of the fingers, and the rest of the fingers parallel to one another, and pointing away from the body. If the thumb shows the velocity of a positive charge in a magnetic field, and the fingers all point in the direction of the magnetic field, then the palm will push in the direction of the force on the positive charge (proton).

From this, we can deduce from the original statement about this proton that the direction of the field is into the screen of this computer. with that field direction held constant, we can work out that

a) if the thumb point down, the force will be to the right

b) if the thumb points to the right, the force will be upwards

c) if the thumb points to the left, the force is downwards

d) if the thumb points into the page, then there will be no force on the proton since the proton must travel perpendicularly to the magnetic field for a force to be induced on it

e) explanation is the same as foe option d.

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