Answer:
the value of t = 0.49 seconds shows that its upward journey
and
at t = 5.43 seconds shows in downward journey
Explanation:
Given:
initial speed, u = 29 m/s
acceleration due to gravity, g = - 9.8 m/s^2
h = 13 m
Let it is moving with velocity v at a height of 13 m.
Use third equation of motion
v² = u² + 2gh
By substituting the values
v² = 29² - (2 * 9.8 * 13)
v = sqrt 585.94
v = 24.2 m/s
Let it takes time t to reach at height 13 m
Use second equation of motion
s = u * t + 1/2 * g * t²
13 = 29t - 4.9t²
4.9t² - 29t + 13 = 0
using quadratic equation to solve time
29 ± [tex]\sqrt{29^2 - 4 * 4.9 * 13}\\[/tex]
t = ------------------------------------
2 * 4.9
t = 5.43 second or t = 0.49 second
Therefore...
the value of t = 0.49 seconds shows that its upward journey
and
at t = 5.43 seconds shows in downward journey
If a bicycle starts from rest and is pedaled normally until the bike is moving at 6 meters per second across level ground, what kinds of energy have its tires been given? (Select all that apply) g
Answer: Translational Kinetic Energy
Rotational Kinetic Energy
Explanation:
An object has translational kinetic energy when it is undergoing through a linear displacement.
Rotational energy is kinetic energy due to the rotation of an object .
Here the wheel of bicycle undergoes both translational and rotational kinetic energy has it moves with linear displacement with rotation in it.
Hence, the tires have been two kinds of energy : translational and rotational kinetic energy
A Young'sdouble-slit interference experiment is performed with monochromatic light. The separation between the slits is 0.44 mm. The interference pattern on the screen 4.2 m away shows the first maximum 5.5 mm from the center of the pattern. What is the wavelength of the light in nm
Answer:
Explanation:
The double slit interference phonemene is described for the case of constructive interference
d sin θ= m λ (1)
let's use trigonometry to find the sinus
tan θ = y / L
in general in interference phenomena the angles are small
tan θ = sin θ / cos θ = sin θ
The double slit interference phonemene is described for the case of constructive interference
d sin θ = m lam (1)
let's use trigonometry to find the sinus
tan θ = y / L
in general in interference phenomena the angles are small
tan θ = sin θ / cos θ = sin θ
we substitute
sin θ = y / L
we substitute in equation 1
d y / L = m λ
λ = dy / L m
let's reduce the magnitudes to the SI system
d = 0.44 mm = 0.44 10⁻³ m
y = 5.5 mm = 5.5 10⁻³ m
L = 4.2m
m = 1
let's calculate
λ = 0.44 10⁻³ 5.5 10⁻³ / (4.2 1)
λ = 5.76190 10-7 m
let's reduce to num
lam = 5.56190 10-7 m (109 nm / 1m)
lam = 556,190 nmtea
we substitute
without tea = y / L
we substitute in equation 1
d y / L = m lam
lam = dy / L m
let's reduce the magnitudes to the SI system
d = 0.44 me = 0.44 10-3 m
y = 5.5 mm = 5.5 10-3
L = 4.2m
m = 1
let's calculate
lam = 0.44 10⁻³ 5.5 10⁻³ / (4.2 1)
lam = 5.76190 10⁻⁷ m
let's reduce to num
lam = 5.56190 10⁻⁷ m (109 nm / 1m)
lam = 556,190 nm
To shoot a swimming fish when an intense light beam from a laser gun you should aim
Answer
aim directly at the image
Explanation
the light from the laser beam will also bend when it hits the air water interface , so aim directly at the fish
a car brakes and stops at 10 [m]. While stopping, the friction force of the wheels on the pavement is 400 [N]. Calculate the work done.
Explanation:
Work = force × distance
W = (400 N) (10 m)
W = 4000 J
A moon orbits a planet along an elliptical path. Which describes the location of the planet within the ellipse
Must be at a focus.
----------------
Hope this helps!
Brainliest would be great!
----------------
With all care,
07x12
One of the two foci of the elliptical route that the moon follows is the planet. The planet will be positioned at one of the two focal points (foci) of an elliptical orbit. The other focus is still vacant.
The two foci are connected by the ellipse's major axis, and for any given ellipse, their separation is constant. The mass of the planet and the mass of the object it orbits—for example, a star if it's a planet in a solar system—are used to calculate the planet's position. The moon revolves the planet in an elliptical pattern due to the gravitational forces between the planet and the object it orbits, with the planet itself at one of the foci.
To know more about elliptical route, here
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a football is kicked toward a goal keeper with an initial speed of 20m/s at an angle of 45 degrees with the horizontal .at the moment the ball is kicked the goal keeper is 50m from the player .at what speed and in what direction must the goalkeeper run in order to catch the ball at the same height at which it was kicked
Answer:
3.18 m/s
Explanation:
Given that
Initial speed of the ball, u = 20 m/s
Angle of inclination, θ = 45°
Distance from the ball, h = 50 m
Using equations of projectile to solve this, we have
We start by finding the time of flight, T
T = 2Usinθ/g
T = (2 * 20 * sin45)/9.8
T = (40 * 0.7071) / 9.8
T = 28.284/9.8
T = 2.89 s
Next we find the Range, R
R = u²sin2θ/g
R = (20² * sin 90) / 9.8
R = (400 * 1) / 9.8
R = 400/9.8 = 40.82 m
Distance the gk must cover
40.82 - 50 m
-9.18 m or 9.18 m in the opposite direction.
Speed of the GK = d/t
9.18 / 2.89 = 3.18 m/s
An alternating current is supplied to an electronic component with a warning that the voltage across it should never exceed 12 V. What is the highest rms voltage that can be supplied to this component while staying below the voltage limit in the warning?
Answer:
The highest rms voltage will be 8.485 V
Explanation:
For alternating electric current, rms (root means square) is equal to the value of the direct current that would produce the same average power dissipation in a resistive load
If the peak or maximum voltage should not exceed 12 V, then from the relationship
[tex]V_{rms} = \frac{V_{p} }{\sqrt{2} }[/tex]
where [tex]V_{rms}[/tex] is the rms voltage
[tex]V_{p}[/tex] is the peak or maximum voltage
substituting values into the equation, we'll have
[tex]V_{rms} = \frac{12}{\sqrt{2} }[/tex] = 8.485 V
An FM radio station transmits a signal with a frequency of 89.1 MHz. Give the wavelength in meters. (use at least three significant digits)
Answer:
3m
Explanation:
89.1 MHz means
89.1×10^6 cycles/second.
Electromagnetic radiation (including radio waves) travel at
3.0×10^8meters/second
Wavelength = Speed/Frequency
The wavelength of a
89.1MHz radio signal is
3.0×10^8/89.1x10^6
= 0.03x10^2
= 3meters
•• A metal sphere carrying an evenly distributed charge will have spherical equipotential surfaces surrounding it. Suppose the sphere’s radius is 50.0 cm and it carries a total charge of (a) Calculate the potential of the sphere’s surface. (b)You want to draw equipotential surfaces at intervals of 500 V outside the sphere’s surface. Calculate the distance between the first and the second equipotential surfaces, and between the 20th and 21st equipotential surfaces. (c) What does the changing spacing of the surfaces tell you about the electric field?
Answer:
Explanation:
For this exercise we will use that the potential is created by the charge inside the equinoctial surface and just like in Gauss's law we can consider all the charge concentrated in the center.
Therefore the potential on the ferric surface is
V = k Q / r
where k is the Coulomb constant, Q the charge of the sphere and r the distance from the center to the point of interest
a) On the surface the potential
V = 9 10⁹ Q / 0.5
V = 18 10⁹ Q
Unfortunately you did not write the value of the load, suppose a value to complete the calculations Q = 1 10⁻⁷ C, with this value the potential on the surfaces V = 1800 V
b) The equipotential surfaces are concentric spheres, let's look for the radii for some potentials
for V = 1300V let's find the radius
r = k Q / V
r = 9 109 1 10-7 / 1300
r = 0.69 m
other values are shown in the following table
V (V) r (m)
1800 0.5
1300 0.69
800 1,125
300 3.0
In other words, we draw concentric spheres with these radii and each one has a potential difference of 500V
C) The spacing of the spheres corresponds to lines of radii of the electric field that have the shape
E = k Q / r²
If an astronomer wants to find and identify as many stars as possible in a star cluster that has recently formed near the surface of a giant molecular cloud (such as the Trapezium cluster in the Orion Nebula), what instrument would be best for her to use
Answer:
Infrared telescope and camera
Explanation:
An infrared telescope uses infrared light to detect celestial bodies. The infrared radiation is one of the known forms of electromagnetic radiation. Infrared radiation is given off by a body possessing some form of heat. All bodies above the absolute zero temperature in the universe radiates some form of heat, which can then be detected by an infrared telescope, and infrared radiation can be used to study or look into a system that is void of detectable visible light.
Stars are celestial bodies that are constantly radiating heat. In order to see a clearer picture of the these bodies, Infrared images is better used, since they are able to penetrate the surrounding clouds of dust, and have located many more stellar components than any other types of telescope, especially in dusty regions of star clusters like the Trapezium cluster.
select the example that best describes a renewable resource.
A.after a shuttle launch, you can smell the jet fuel for hours.
B.solar panels generate electricity that keeps the satellites running.
C.tractor trailers are large trucks that run on diesel fuel.
D. we use our barbeque every night; it cooks with propane.
Answer:
B.solar panels generate electricity that keeps the satellites running.
Explanation:
Solar panels are a renewable resource because they take energy from the sun.
What is the relationship between the surface area of a parachute and the amount of air resistance it builds up when it is deployed by a sky diver?
Answer:
An open parachute increases the cross-sectional area of the falling skydiver and thus increases the amount of air resistance which he encounters. Once the parachute is opened, the air resistance overwhelms the downward force of gravity.
Explanation:
The larger a parachute, the greater the force.
Hope it helps you in a little way.
A string on the violin has a length of 24.20 cm and a mass of 0.0992 g. The fundamental frequency of the string is 659.3 Hz.
Required:
a. What is the speed of the wave on the string?
b. What is the tension in the string?
Answer:
a. The speed of the wave is 319.1m
b. The tension in the string is 41.74N
Explanation:
Please see the attachments below
The angle between the axes of two polarizing filters is 41.0°. By how much does the second filter reduce the intensity of the light coming through the first?
Answer:
The amount by which the second filter reduces the intensity of light emerging from the first filter is
z = 0.60
Explanation:
From the question we are told that
The angle between the axes is [tex]\theta = 41^o[/tex]
The intensity of polarized light that emerges from the second filter is mathematically represented as
[tex]I= I_o cos^2 \theta[/tex]
Where [tex]I_o[/tex] is the intensity of light emerging from the first filter
[tex]I = I_o [cos(41.0)]^2[/tex]
[tex]I =0.60 I_o[/tex]
This means that the second filter reduced the intensity by z = 0.60
The voltage across the terminals of an ac power supply varies with time according to V=V0cos(t). The voltage amplitude is V0 = 41.0V .
A. What is the root-mean-square potential difference Vrms?
B. What is the average potential difference Vav between the two terminals of the power supply?
Answer:
A) V_rms = 29 V
B) Vav = 0 V
Explanation:
A) We are told that;
V = V_o cos ωt
voltage amplitude; V = V_o = 41.0V
Now, the formula for the root-mean-square potential difference Vrms is given as;
V_rms = V/√2
Thus plugging in relevant values, we have;
V_rms = 41/√2
V_rms = 29 V
B) Due to the fact that the voltage is sinusoidal from the given V = V_o cos ωt, we can say that the average potential difference Vav between the two terminals of the power supply would be zero.
Thus; Vav = 0 V
A. The root-mean-square potential difference ([tex]V_{rms}[/tex]) is equal to 28.99 Volts.
B. For this voltage with a sinusoidal waveform (sine wave), the average potential difference ([tex]V_{ave}[/tex]) between the two terminals of the power supply is equal to zero (0).
Given the following data:
Voltage amplitude = 41.0 Volts.The voltage across the terminals of an alternating current (AC) power supply varies directly with time according to the equation:
[tex]V_0 = V_0cos(t)[/tex]
A. To find the root-mean-square potential difference ([tex]V_{rms}[/tex]):
Mathematically, root-mean-square for voltage in an alternating current (AC) power supply (circuit) is given by the formula:
[tex]V_{rms} = \frac{V}{\sqrt{2} }[/tex]
Substituting the given parameter into the formula, we have;
[tex]V_{rms} = \frac{41}{\sqrt{2} }\\\\V_{rms} = \frac{41}{1.4142 }\\\\V_{rms} = 28.99\; Volts[/tex]
B. To find the average potential difference ([tex]V_{ave}[/tex]) between the two terminals of the power supply:
For this voltage with a sinusoidal waveform (sine wave), the average potential difference ([tex]V_{ave}[/tex]) between the two terminals of the power supply is equal to zero (0).
Read more: https://brainly.com/question/15121836
Which equations are used to calculate the velocity of a wave? velocity = distance × time velocity = wavelength × frequency velocity = distance/time velocity = wavelength/frequency velocity = distance/time velocity = wavelength × frequency velocity = distance × time velocity = wavelength/frequency
Answer:
velocity = distance/time
velocity = wavelength × frequency
Both of these are commonly known equations to calculate velocity with different variables.
If you were in a smooth-riding train with no windows, could you sense the difference between uniform motion and rest or between accelerated motion and rest?
1. Both acclerated and uniform motion can be sensed.
2. Only uniform motion can be sensed.
3. Only accelerated motion can be sensed.
4. No motion can be sensed.
Answer:
3. Only accelerated motion can be sensed
Explanation:
Without windows on such a train, you'd have no frame of reference for your speed. By that I mean, without being able to see how fast you are moving past other things, it's almost as if you aren't moving at all... almost.
At rest you obviously aren't moving and in uniform motion, with a constant speed, it would feel as though you aren't moving. But during periods of acceleration you'll feel the force on your body (F=ma) and would be able to tell if you were moving in a particular direction.
You've probably felt this before. Maybe not on a windowless train but perhaps in a car or on a roller coaster. Speeding up makes you go back into your seat a bit and slowing down makes you lean forward a bit. Both speeding up and slowing down are examples of acceleration (just in different directions) and how fast you accelerate will affect how much force you experience.
So the answer would be option 3.
Side note: If the train wasn't smooth riding then there would be some amount of friction going on and you could probably tell if you were in motion by the products of that friction (like sound and vibrations) even at a constant speed.
Consider a house at sea level that has 2500 square feet of floor area. What is the total force that the air inside the house exerts upward on the ceiling
Answer:
Total Force that the air inside the house exerts upward on the ceiling is 5.25 × 10⁶ lb
Explanation:
Force = Atmospheric Pressure × Floor Area
Where; Standard Atmospheric Pressure = 2100 lb/ft²
Floor Area = 2500 ft²
Substitute the data
∴ Total Force = 2100 lb/ft² × 2500 ft²
Total Force = 5.25 × 10⁶ lb
A dust particle on a phonograph record rotates at a speed of 45 revolutions per minute if the particle is 10 cm from the axis of rotation. Find. 1) its linear speed and linear acceleration.
Explanation:
ω = 45 rev/min × (2π rad/rev) × (1 min / 60 s) = 4.71 rad/s
r = 10 cm = 0.10 m
1) The linear speed is:
v = ωr
v = (4.71 rad/s) (0.10 m)
v = 0.471 m/s
2) The linear acceleration in the tangential direction is 0.
The linear acceleration in the radial direction is:
a = v² / r
a = (0.471 m/s)² / (0.10 m)
a = 2.22 m/s²
qual charges, one at rest, the other having a velocity of 104 m/s, are released in a uniform magnetic field. Which charge has the largest force exerted on it by the magnetic field?
Answer:
The correct option is D
Explanation:
From the question we are told that
The speed of the first charge is [tex]v = 0 \ m/s[/tex]
This is because it is at rest
The speed of the second charge is [tex]v = 10^{4} \ m/s[/tex]
Generally the force exerted by a magnetic field on a charge is mathematically represented as
[tex]F_q = q * v * B sin \theta[/tex]
Now looking at this above equation we can see that [tex]F_q[/tex] can only be maximum at [tex]\theta = 90 ^o[/tex] and this only obtained when the direction of the charge (i.e its velocity ) is perpendicular to the direction of the magnetic field
so the correct option for this question is D
1. A força de atração eletrostática é responsável pela união dos íons, onde cargas elétricas de sinais opostos se atraem. Falando a um nível microscópico, tal atração entre os íons acaba produzindo aglomerados com formas geométricas bem definidas, representados pela figura a seguir: Qual a melhor definição para essa estrutura iônica e que composto é formado a partir dela? * 1 ponto cristais de sal / cloreto de potássio. cristal com face plana / cloreto de cálcio. retículo cristalino / cloreto de sódio. retículo de ligações / clorato de sódio.
Answer:
estrutura cristalina / cloreto de sódio
Explicação:
O cloreto de sódio forma a estrutura cristalina da treliça. Nesta estrutura, um átomo de sódio é cercado por 6 íons de carga oposta. Os íons opostos são negativos porque o sódio perde elétrons, o que o torna ião carregado positivamente chamado cátion, de modo que 6 íons negativos estão presentes ao redor do sódio. A estrutura cristalina também é conhecida como cúbico simples, o que significa que eles são distribuídos em três dimensões com igual distância entre eles e formando um ângulo de 90 graus.
In the 1980s, the term picowave was used to describe food irradiation in order to overcome public resistance by playing on the well-known safety of microwave radiation. Find the energy in MeV of a photon having a wavelength of a picometer.
Answer:
E = 1.24MeV
Explanation:
The photon travels at the speed of light, 3.0 × [tex]10^{8}[/tex] m/s, and given that its frequency = 1 picometer = 1.0 × [tex]10^{-12}[/tex] m.
Its energy can be determined by;
E = hf
= (hc) ÷ λ
where E is the energy, h is the Planck's constant, 6.626 × [tex]10^{-34}[/tex] Js, c is the speed of the light and f is its frequency.
Therefore,
E = (6.626 × [tex]10^{-34}[/tex]× 3.0 × [tex]10^{8}[/tex]) ÷ 1.0 × [tex]10^{-12}[/tex]
= 1.9878 × [tex]10^{-25}[/tex] ÷ 1.0 × [tex]10^{-12}[/tex]
E = 1.9878 × [tex]10^{-13}[/tex] J
But, 1 eV = 1.6 × [tex]10^{-19}[/tex] J. So that;
E = [tex]\frac{1.9878*10^{-13} }{1.6*10^{-19} }[/tex]
= 1242375 eV
∴ E = 1.24MeV
The energy of the photon is 1.24MeV.
a small bar magnet is suspended horizontally by a string. When placed in a uniform horizontal magnetic field, it will
Answer:
It will neither translate in the opposite direction nor .rotate so as to be at right angles, it will also neither rotate so as to be vertical direction
A solid block is attached to a spring scale. When the block is suspended in air, the scale reads 20.1 N; when it is completely immersed in water, the scale reads 15.3 N.
A) What is the volume of the block?
B) What is the density of the block?
Answer:
A) [tex]V = 4.92 \cdot 10^{-4} m^{3} = 492 cm^{3}[/tex]
B) [tex] d = 4181.49 kg/m^{3} = 4.18 g/cm^{3} [/tex]
Explanation:
A) Using the Archimedes' force we can find the weight of water displaced:
[tex] W_{d} = W_{a} - W_{w} [/tex]
Where:
[tex]W_{a}[/tex]: is the weight of the block in the air = 20.1 N
[tex]W_{w}[/tex]: is the weight of the block in the water = 15.3 N
[tex] W_{d} = W_{a} - W_{w} = 20.1 N - 15.3 N = 4.8 N [/tex]
Now, the mass of the water displaced is:
[tex] m = \frac{W_{d}}{g} = \frac{4.8 N}{9.81 m/s^{2}} = 0.49 kg [/tex]
The volume of the block can be found using the mass of water displaced and the density of the water:
[tex]V = \frac{m}{d} = \frac{0.49 kg}{997 kg/m^{3}} = 4.92 \cdot 10^{-4} m^{3} = 492 cm^{3}[/tex]
B) The density of the block can be found as follows:
[tex] d = \frac{W_{a}}{g*V} = \frac{20.1 N}{9.81 m/s^{2}*4.92 \cdot 10^{-4} m^{3}} = 4181.49 kg/m^{3} = 4.18 g/cm^{3} [/tex]
I hope it helps you!
A small barge is being used to transport trucks across a river. If the barge is 10.00 m long by 8.00 m wide and sinks an additional 3.75 cm into the river when a loaded truck pulls onto it, determine the weight of the truck and load.
Answer: Weight truck+load = 29.4×[tex]10^{3}[/tex] N
Explanation: When an object floats in a fluid, there is an upward force, caused by the liquid, acting on the object that opposes the weight of the immersed object. This force is called Buyoyant Force and is determined by:
B = d*V*g
where
d is density of the fluid;
V is volume of liquid displaced due to the immersed object;
g is acceleration due to gravity;
For the truck, the system is in equilibrium, which means buyoyant force is equal weight. Then:
Volume displaced is
V = 10*8*0.0375
V = 3 [tex]m^{3}[/tex]
Density of water: 1000kg/[tex]m^{3}[/tex]
[tex]F_{P} = F_{B}[/tex]
[tex]F_{P}[/tex] = 1000*3*9.8
[tex]F_{P}[/tex] = 29.4×[tex]10^{3}[/tex] N
The weight of the truck and the load is 29.4×[tex]10^{3}[/tex] Newtons
An electron is accelerated through 2.35 103 V from rest and then enters a uniform 2.30-T magnetic field. (a) What is the maximum magnitude of the magnetic force this particle can experience
the maximum magnitude is 5.5
Will give brainliest ASAP! Please help (1/10 questions, will mark 5 stars and brainliest for all answers if correct)
Answer:
Option (A)
Explanation:
A 20 kg boy chases the butterfly with a speed of 2 meter per second.
Angle at which he runs is 70° North of West.
Therefore, Horizontal component (Vx) directing towards West will be,
Vx = v(Cos70°)
Vy = v(Sin70°)
Since momentum of a body is defined by,
Momentum = Mass × Velocity
Therefore, Westerly component of the momentum will be,
Momentum = 20 × (v)(Cos70°)
= 20 × 2Cos70°
= 13.68
≈ 13.7 kg-meter per second
Therefore, Option (A) will be the answer.
A 3 kg rock is swung in a circular path and in a vertical plane on a 0.25 m length string. At the top of the path, the angular velocity is 11 rad/s. What is the tension in the string at that point
Answer:
The tension in the string at that point is 90.75 N
Explanation:
Given;
mass of the object, m = 3 kg
length of string, r = 0.25 m
the angular velocity, ω = 11 rad/s
The tension on string can be equated to the centrifugal force on the object;
T = mω²r
Where;
T is the tension in the string
m is mass of the object
ω is the angular velocity
r is the radius of the circular path
T = 3 x (11)² x 0.25
T = 90.75 N
Therefore, the tension in the string at that point is 90.75 N
Estimate the peak electric field inside a 1.2-kW microwave oven under the simplifying approximation that the microwaves propagate as a plane wave through the oven's 700-cm2 cross-sectional area.
Answer:
The peak electric field is [tex]E_o = 3593.6 V/m[/tex]
Explanation:
From the question we are told that
The power is [tex]P = 1.2 \ kW = 1.2 *10^{3} \ W[/tex]
The cross-sectional area is [tex]A = 700 \ cm^2 = 700 *10^{-4} \ m^2[/tex]
Generally the average intensity of the microwave is mathematically represented as
[tex]I = \frac{c * \epsilon _o * E_o^2 }{2}[/tex]
Where [tex]c[/tex] is the speed of light with value [tex]c = 3.0 *10^{8} \ m/s[/tex]
and [tex]\epsilon_o[/tex] is the permitivity of free space with value [tex]\epsilon_o = 8.85*10^{-12} \ m^{-3} \cdot kg^{-1}\cdot s^4 \cdot A^2[/tex]
also [tex]E_o[/tex] is the peak electric field.
Now making [tex]E_o[/tex] the subject [tex]E_o = \sqrt{\frac{2 * I }{ c * \epsilon _o } }[/tex]
But this intensity of the microwave can also be represented mathematically as
[tex]I = \frac{ P }{A }[/tex]
substituting values
[tex]I = \frac{ 1.2 *10^{3} }{700 *10^{-4} }[/tex]]
[tex]I = 17142.85 \ W/m^2[/tex]
So
[tex]E_o = \sqrt{\frac{2 * 17142.85 }{ 3.0*10^{8}] * 8.85*10^{-12} } }[/tex]
[tex]E_o = 3593.6 V/m[/tex]
The peak electric field of the microwave is 3,593.1 V/m.
The given parameters;
power of the wave, P = 1.2 kW = 1,200 Warea of the plane, A = 700 cm²The intensity of the wave is calculated as follows;
[tex]I = \frac{P}{A} \\\\I = \frac{1,200}{700 \times 10^{-4}} \\\\I = 17,142.86 \ W/m^2[/tex]
The peak electric field is calculated as follows;
[tex]E_o = \sqrt{\frac{2I}{c \varepsilon _o} } \\\\E_o = \sqrt{\frac{2\times 17,142.86}{3\times 10^8 \times 8.85 \times 10^{-12}} } \\\\E_o = 3,593.1 \ V/m[/tex]
Thus, the peak electric field of the microwave is 3,593.1 V/m.
Learn more here:https://brainly.com/question/12531491
Suppose that a 0.275 m radius, 500 turn coil produces an average emf of 11800 V when rotated one-fourth of a revolution in 4.42 ms, starting from its plane being perpendicular to the magnetic field.
Required:
Find the magnetic field strength needed to induce an average emf of 10,000 V.
Answer:
The magnetic field strength : 0.372 T
Explanation:
The equation of the induced emf is given by the following equation,
( Equation 1 ) emf = - N ( ΔФ / Δt ) - where N = number of turns of the coil, ΔФ = change in the magnetic flux, and Δt = change in time
The equation for the magnetic flux is given by,
( Equation 2 ) Ф = BA( cos( θ ) ) - where B = magnetic field, A = area, and θ = the angle between the normal and the magnetic field
The area of the circular coil is a constant, as well as the magnetic field. Therefore the change in the magnetic flux is due to the angle between the normal and the magnetic field. Therefore you can expect the equation for the change in magnetic flux to be the same as the magnetic flux, but only that there must be a change in θ.
( Equation 3 ) ΔФ = BA( Δcos( θ ) )
Now as the coil rotates one-fourth of a revolution, θ changes from 0 degrees to 90 degrees. The " change in cos θ " should thus be the following,
Δcos( θ ) = cos( 90 ) - cos( 0 )
= 0 - 1 = - 1
Let's substitute that value in the third equation,
( Substitution of Δcos( θ ) previously, into Equation 3 )
ΔФ = BA( - 1 ) = - BA
Remember the first equation? Well if the change in the magnetic flux = - BA, then through further substitution, the emf should = - N( - BA ) / Δt. In other words,
emf = - N( - BA ) / Δt,
emf = NBA / Δt,
B = ( emf )Δt / NA
Now that we have B, the magnetic field strength, isolated, let's solve for the area of the circular coil and substitute all known values into this equation.
Area ( A ) = πr²,
= π( 0.275 )² = 0.2376 m²,
B = ( 10,000 V )( 4.42 [tex]*[/tex] 10⁻³ s ) / ( 500 )( 0.2376 m² ) = ( About ) 0.372 T
The magnetic field strength : 0.372 T