1. How fast is a radio wave traveling if it is 4.0 meters long and its frequency is
82 Hz?

Answers

Answer 1

Answer:

Speed = 328 m/s

Explanation:

Given the following data:

Wavelength = 4 m

Frequency = 82 Hz

To find the speed of the radio wave;

Speed = wavelength * frequency

Speed = 4 * 82

Speed = 328 m/s

Therefore, the radio wave is travelling at 328 meters per seconds.

Radio waves can be defined as an electromagnetic wave that has its frequency ranging from 30 GHz to 300 GHz and its wavelength between 1mm and 3000m. Therefore, radio waves are a series of repetitive valleys and peaks that are typically characterized of having the longest wavelength in the electromagnetic spectrum.


Related Questions

On the graph of voltage versus current, how do the resistors compare?

Answers

It would e letter D hope you have a good day

A house brick has a volume of 1900 cm³ and a weight in air of 80N.What is its apparent weight in water?The density of water is 1.00 g cm³?​

Answers

Answer:

61 N

Explanation:

We'll begin by calculating the mass of the brick when placed in water. This can be obtained as follow:

Volume of brick = 1900 cm³

Density of water = 1 g/cm³

Mass of brick in water =…?

Density = mass / volume

1 = mass of brick in water / 1900

Cross multiply

Mass of brick in water = 1 × 1900

Mass of brick in water = 1900 g

Next, we shall convert 1900 g to Kg.

1000 g = 1 Kg

Therefore,

1900 g = 1900 g × 1 Kg / 1000 g

1900 g = 1.9 Kg

Next, we shall determine the weight in water. This can be obtained as follow:

Mass (m) = 1.9 Kg

Acceleration due to gravity (g) = 10 m/s²

Weight (W) =?

W = m × g

W = 1.9 × 10

W = 19 N

Thus, the weight of the brick in water is 19 N.

Finally, we shall determine the apparent weight of the brick in water. This can be obtained as follow:

Weight in air = 80 N

Weight in water = 19 N

Apparent weight =?

Apparent weight = weight in air – weight in water

Apparent weight = 80 – 19

Apparent weight = 61 N

what part of the rocket reaches space

Answers

Answer:

7

Explanation:

There is really no explanation needed

Please help 23 also 29 the answer choices are reflection or refraction your fraction absorption

Answers

Answer:

23. Option B. Hertz

29. Refraction.

Explanation:

23. Determination of the unit of measurement of frequency.

Frequency is simply defined as the number of oscillation made in one second. Mathematically, frequency can be represented as:

Frequency = 1/period

f = 1/T

Period is measured in seconds.

Thus, the unit of frequency becomes

f = 1/T

f = 1/s = s¯¹ (Hertz)

Therefore, the unit of frequency is Hertz.

29. When a wave enters a new medium, the speed of the wave is uttered. This leads to the bending of the wave. When this occurs, we can say refraction has taken place.

- Is the kinetic energy conserved in the collision between
the ball and the pendulum?

Answers

Answer:

No, Momentum is conserved.

Explanation:

The ballistic pendulum is a device in which a projectile such as a bullet is fired into a suspended heavy wooden stationary block. Some kinetic energy gets transformed into heat and sound, and some is used to deform the block. However, momentum is conserved.

a large heavy truck and a baby carriage roll down a hill. Neglecting friction, at the bottom of the hill, the baby carriage will likely have A. less momentum, B. about the same momentum, C. more momentum or D. double the momentum of the truck​

Answers

Answer:

please give me brainlist and follow

Explanation:

At the bottom of the hill, the baby carriage will likely have less momentum Therefore, option D is correct. Solution: ... Therefore, at the bottom of the hill, the heavy truck will have more momentum and baby carriage will have less momentum.

PLS HELP, WILL GIVE BRAINLIEST!!!
A piece of clay with a mass of 350 g is dropped to the floor from a height of 1.5 m (A). Calculate the KE and PE of the clay at

a. (A = 1.5 m).
b. (B = 70 cm), and
c. (C = 0 m, just before hitting the ground). d. Make an energy graph at each point​

Answers

Answer:

b bro it's b bro

Tendons are, essentially, elastic cords stretched between two fixed ends; as such, they can support standing waves. These resonances can be undesirable. The Achilles tendon connects the heel with a muscle in the calf. A woman has a 20-cm long tendon with a cross-section area of 130 mm^2. The density of tendon tissue is 1100 kg/m^3.

Required:
For a reasonable tension of 600 , what will be the fundamental resonant frequency of her Achilles tendon?

Answers

Answer:

161.938 Hz

Explanation:

the computation of the fundamental resonant frequency is shown below

p = 1100 kg/m^3

A = 130 mm^2

= 130 ×10^-6 m^2

T = 600 N

L = 20 cm

= 0.2 m

Now the linear density of tendon is

=  1100 kg/m^3 ×  130 ×10^-6

= 0.143 kg/m

Now the wave of the string is

= √600  ÷ √0.143

= 64.775 m/s

Now finally the fundamental resonant frequency is

= 64.775 ÷ (2 × 0.2)

=161.938 Hz

When measuring speed of sound in air, speed of light = 4f(length of column of air + 0.3 * diameter of tube).
Why is multiplied by 4?
Where does the 4 come from?​

Answers

Answer:

the length of the column in air

Sheryl always expects special treatment wherever she goes because, after all, she is better than everyone else. She could care less how others feel and routinely expects people to worship her. These attributes are typical of ______.

Answers

Explanation:

it attributes to Being pride of herself

Why would ash from a volcano make the temperature drop?

Answers

First, volcanic eruptions produce major quantities of carbon dioxide (CO2), a gas known to contribute to the greenhouse effect. ... The small ash particles decrease the amount of sunlight reaching the surface of the earth and lower average global temperatures.

The best leaper in the animal kingdom is the puma, which can jump to a height of 3.7m when leaving the ground at an angle of 45 degrees. with what speed must the animal leave the ground to reach that height?

Answers

Answer:

v = 12 m/s

Long, boring, and convoluted explanation:

First, let's lay out our information.

- max height = 3.7 m

- 0 = 45°

- gravitational acceleration constant = 9.8 [tex]\frac{m}{s^2}[/tex]

Since the puma leaves the ground at a 45 ° angle, its motion will follow a curved path as seen in many projectile motion problems, where the object is being influenced solely by the force of gravity. And because the puma leaves the ground at an angle, its initial velocity is broken down into its horizontal and vertical components. We were also told, though indirectly, that the max height is  3.7m  because the puma can reach up to that height. Gravity is always given to be 9.8 [tex]\frac{m}{s^2}[/tex]

Because we are dealing with maximum height and gravity, we have to use the vertical component of the velocity,  vsin ( θ ) , and not the horizontal component, vcos ( θ ) .

Given its max height, the acceleration due to gravity, and the angle, we can now solve for the speed at which the puma leaves the ground using the following equation: vsin ( θ )  = [tex]\sqrt{2hg}[/tex]

Where vsin ( θ )  is the vertical component of the initial velocity and h  and g are max height and gravitational acceleration constant respectively.

Plugin, rearrange and solve

v sin ( θ )  =  [tex]\sqrt{2hg}[/tex]

v sin ( 45 ∘ )  =   √ 2  ×  3.7  ×  9.8

v ( 0.71 )  =  [tex]\sqrt{72.52}[/tex]

v ( 0.71 )  =  8.52

v  =  8.52 /0.71

v =  12 m s

How does a sound wave's amplitude affect the sound we hear? How does a sound
wave's frequency affect the sound we hear?

Answers

Answer:

cause we hear differently

Explanation:

Answer:

As the amplitude of the sound wave increases, the intensity of the sound increases. Sounds with higher intensities are perceived to be louder. Relative sound intensities are often given in units named decibels (dB)

A person is dragging a packing crate of mass 74.9 kg across a rough horizontal floor where the coefficient of kinetic friction is 0.35. He exerts a force F at and angle 43.0 degrees above the horizontal. What is the Force F such that the crate moves at a constant speed

Answers

Answer:

351.28 N

Explanation:

Let F be the force on the object and f be the frictional force. The component of the force acting in the horizontal direction causing the object to move is FcosФ where Ф is the angle between F and the horizontal = 43.0°. The frictional force on the packing crate f = μN where μ = coefficient of kinetic friction = 0.35 and N = normal force = W = weight of the packing crate = mg where m = mass of crate = 74.9 kg and g = acceleration due to gravity = 9.8 m/s².  So, f = μN = μW = μmg

So, the net force on the packing crate is

FcosФ - f = ma

FcosФ - μmg = ma

Since the crate moves at constant speed, its acceleration a = 0

So, FcosФ - μmg = ma

FcosФ - μmg = m(0)

FcosФ - μmg = 0

FcosФ = μmg

F = μmg/cosФ

Substituting the values of the variables into the equation, we have

F = μmg/cosФ

F = 0.35 × 74.9 kg × 9.8 m/s²/cos43.0°

F = 256.907 kg-m/s²/0.73135

F = 351.28 kg-m/s²

F = 351.28 N

Some fundamental particles such as quarks (and some leptons, such as the electron) have an electric charge and use photons as mediating particles to communicate with other particles with electric charge. Similarly, quarks, identified by their color charge, use a mediating particle to interact with other particles with color charge, that is, other quarks. What is the particle that mediates interactions among quarks

Answers

Answer: hello the options to your question is missing below are the missing

options :

the W boson the gluon the Z boson the tau particle

answer : The Gluon ( option 2 )

Explanation:

The particle that mediates the interactions between quarks is known as the Gluon.

Gluon is known as an elementary particle that acts as the exchange particle between quarks. It's function is similar to the activity involving the exchange of photons in the electromagnetic force involving  two charged particles

How does density affect refraction

Answers

Answer:

please give me brainlist and follow

Explanation:

The angle and wavelength at which the light enters a substance and the density of that substance determine how much the light is refracted. ... When light passes from a more dense to a less dense substance, (for example passing from water into air), the light is refracted (or bent) away from the normal.

An astronomy class is so excited by the discovery of planets around other stars that they decide to do a library exhibit on the subject so that everyone in the school can learn about it. In this exhibit they want to pay tribute to both the astronomers of today who have done the work AND some of the scientists of the past whose work was essential to making the discoveries possible (and directly related to the techniques involved). Which of the following scientists of the past should definitely be included in the exhibit?
George Herbig  Ejnar Hertzsprung  Ptolemy 
Gerard Kuiper  Christian Doppler 

Answers

Answer:

Christian Doppler

Explanation:

The Scientist with the most significant contribution to the discovery of planets around other stars is Christian Doppler and his work that made this discovery possible is the Principle of  DOPPLER EFFECT

Christian Doppler was an Austrian scientist and physicist whose principle Doppler effect explained how observed frequency of light and sound waves are affected by a relative motion of both the source and detector

A capacitor is constructed of two large, identical, parallel metal plates separated by a small distance d

a. True
b. False

Answers

i think its true i dont kno for sure

pls help giving brainliest!
• Explain how Ohm's Law is like a river.
o What represents Voltage?
o What represents Current?
o What represents Resistance?​

Answers

Answer:

Pressure of water = Voltage

Flow rate of water = Current

Obstructions present in the river = Resistance

Explanation:

We can describe Ohm's Law by using the river analogy,

The flow of water from a mountain to lower parts can be considered as change from high potential to a lower potential.The flow of water can also be considered as flow of electrons, that is current in a circuitThere are also obstructions in rivers that can be considered as resistance in an electric circuit.

Rudy plans to conduct an experiment using three rosebushes of the same variety and size. His hypothesis is that the plant
receiving the most sunlight at the end of three months will show the most growth. In his plan below, he has listed how much
water, fertilizer, and sunlight each plant will receive. Why is his experiment flawed?

Answers

Answer: B) He has too many independent variables.

Explanation: Nothing in the experiment is a constant or being measured.

A graph of a wave is shown if the frequency f is 8.0 Hz what is the waves speed

Answers

Answer:

C

[tex]6 = \frac{3}{2} \lambda \\ wavelength : \: \lambda = 4 \: m \\ from \: wave \: equation \\ v = f\lambda \\ v = 8 \times 4 \\ v = 24 \: {ms}^{ - 1} [/tex]

The speed of the waves will be =  [tex]24\dfrac{m}{s}[/tex]

Given data is frequency f = 8.0 Hz

What will be the speed of the wave?

As we know that the speed of the wave is given by the formula below

[tex]V=f\times \lambda[/tex]

Since

[tex]6=2 \lambda[/tex]

[tex]\lambda =3m[/tex]

now

[tex]V=8\times3[/tex]

[tex]V=24m[/tex]

The speed of the waves will be = [tex]24\dfrac{m}{s}[/tex]

To know more about waves speed follow

https://brainly.com/question/13761336

Discuss how planck's hypothesis explain the observed blackbody spectrum.​

Answers

Answer:

Planck's radiation law, a mathematical relationship formulated in 1900 by German physicist Max Planck to explain the spectral-energy distribution of radiation emitted by a blackbody (a hypothetical body that completely absorbs all radiant energy falling upon it, reaches some equilibrium temperature, and then reemits

Explanation:

An electromagnetic wave has a frequency of 1.0 x 10^5. What is the wavelength of the wave?

Answers

Answer:

The frequency , speed and wavelength of an electromagnetic wave are related by the formula

Speed = frequency x wavelength

frequency = speed / wavelength

substituting the values

frequency = 3 x #10 ^8# m /s / 1 x #10^15# m

= 3 x #10^-7# /s

The wavelength of the wave will be 3000 m. The relationship between the wave's wavelength, time, and speed is used to solve the problem.

What is wavelength?

The distance between two successive troughs or crests is known as the wavelength. The peak of the wave is the highest point, while the trough is the lowest.

The given data in the problem is;

[tex]\lambda[/tex] is the wave's wavelength

c denotes the wave's speed=3×10⁸ m/secv

v is the frequency = 1 ×10⁵ Hz

The relationship between the wave's wavelength, time, and speed is given as

[tex]\rm \lambda = \frac{c}{v} \\\\ \rm \lambda = \frac{3 \times 10^8}{1.0 \times 10^5} \\\\ \lambda=30000 \ m[/tex]

Hence the wavelength of the wave will be 3000 m.

To learn more about the wavelength refer to the link;

brainly.com/question/7143261

Someone please help me! And I will mark you as brainlist!!

1) A ball with a mass of 2.0 kg is thrown upward 1.2m calculate its gravitational potential energy into two significant figures. Gravity = 9.8 N/kg

• 2.4 J
• 1.4 J
• 120 J
• 24 J


2) Translation kinetic energy is defined as the energy of a system due to the motion of the system’s...

• center of mass
• axis of symmetry
• molecules
• rotational movement

PLEASE HELP!!

Answers

Answer:

1. G.P.E = 24 J

2. center of mass

Explanation:

Given the following data;

Mass = 2kg

Height, h = 1.2m

Acceleration due to gravity = 9.8 N/kg or m/s².

To find the gravitational potential energy;

Gravitational potential energy (GPE) is an energy possessed by an object or body due to its position above the earth.

Mathematically, gravitational potential energy is given by the formula;

[tex] G.P.E = mgh[/tex]

Where;

G.P.E represents potential energy measured in Joules.m represents the mass of an object. g represents acceleration due to gravity measured in meters per seconds square. h represents the height measured in meters.

Substituting into the formula, we have;

[tex] G.P.E = 2*1.2*9.8 [/tex]

G.P.E = 23.52 to 2 S.F = 24 Joules.

Translation kinetic energy is defined as the energy of a system due to the motion of the system’s center of mass. The center of mass is typically where the mass of the object or particle is concentrated.

PLEASE HELP! URGENT

Explain how the forces need to change so an aeroplane can land

Answers

Answer:

it changes by taking the air from below the plane and curving it to the top causing draw wich slows it down then the weight that pulls it down to land.

please put me brainliest

Explanation:

Your spaceship lands on a moon of a small planet that orbits a distant star. As you initially circled the moon, you measured its diameter to be 5480 km. After land you observe that a simple pendulum that had a frequency of 3.50 Hz on Earth now has a frequency of 1.82 Hz. What is the mass of the moon

Answers

Answer:

[tex]m=3*10^2^3kg[/tex]

Explanation:

From the question we are told that:

Moon diameter [tex]D_m=5480Km \approx 2740000m[/tex]

Earth's frequency [tex]F_e=3.50Hz[/tex]

Planet's frequency [tex]F_p=1.80Hz[/tex]

 

Generally the equation for Frequency and Gravity relationship is mathematically given by

[tex]\frac{F_p}{F_e}=\sqrt{ \frac{g_p}{g_e} }[/tex]

Therefore  gravity of Moon  is given as

[tex]g_p= g_e*(\frac{f_p}{f_e} )^2[/tex]

[tex]g_p= 9.8*(\frac{1.82}{3.50} )^2[/tex]

[tex]g_p=2.64992m/s^2[/tex]

Generally the equation for mass of spherical body is mathematically given by

[tex]m=\frac{g_pD_m^2}{G}[/tex]

where G= gravitational constant

[tex]m=\frac{2.64992m/s^2*(2740000m)^2}{6.67*10^{-11}}[/tex]

[tex]m=2.98268956*10^2^3kg[/tex]

[tex]m=3*10^2^3kg[/tex]

Suppose that you'd like to find out if a distant star is moving relative to the earth. The star is much too far away to detect any change in its brightness as it moves toward or away from the earth. Instead we can use the Doppler effect to determine its relative speed. For this problem we are going to look at the spectral lines from hydrogen, specifically the one with a wavelength of 656.46 nm.

Required:
What is V(star) , the speed at which the star is moving relative to the earth?

Answers

Answer:

The speed will be "18km/s". A further explanation is given below.

Explanation:

According to the question, the values are:

Wavelength,

[tex]\lambda = 656.46 \ nm[/tex]

[tex]\Delta \lambda = 0.04[/tex]

[tex]c=3\times 10^8[/tex]

As we know,

⇒  [tex]\frac{\Delta \lambda}{\lambda} =\frac{v}{c}[/tex]

On substituting the values, we get

⇒  [tex]\frac{656.46}{0.04} =\frac{v}{3\times 10^8}[/tex]

⇒         [tex]v=\frac{656.46}{0.04} (3\times 10^8)[/tex]

⇒            [tex]=16411.5\times 3\times 10^8[/tex]

⇒            [tex]=18280 \ m/s[/tex]

or,

⇒            [tex]=18 \ km/s[/tex]

The  speed at which the star is moving relative to the earth is 18 km/s

Calculation of the speed:

Since the wavelength is  656.46 nm.

And, Δλ=0.04nm

Here Wavelength should represent the distance between the same points in the cycles of a signal propagated in space or it should be along a wire.

Now the speed should be

[tex]= 0.04 \div 656.46 \times 3 \times 10^8[/tex]

= 1820m/s

= 18 km.s

Therefore, The  speed at which the star is moving relative to the earth is 18 km/s

learn more about speed here: https://brainly.com/question/24692367

In an attempt to reduce the extraordinarily long travel times for voyaging to distant stars, some people have suggested traveling at close to the speed of light. Suppose you wish to visit the red giant star Betelgeuse, which is 430 lyly away, and that you want your 20,000 kgkg rocket to move so fast that you age only 36 years during the round trip.
A. How fast (v) must the rocket travel relative to earth?
B. How much energy is needed to accelerate the rocket to this speed?
C. How many times larger is this energy than the total energy used by the United States in the year 2000, which was roughly 1.0 x 10^20 J?

Answers

Answer:

a) [tex]v=0.999124c[/tex]

b) [tex]E=7.566*10^{22}[/tex]

c) [tex]E_a=760 times\ larger[/tex]

Explanation:

From the question we are told that

Distance to Betelgeuse [tex]d_b=430ly[/tex]

Mass of Rocket [tex]M_r=20000[/tex]

Total Time in years traveled [tex]T_d=36years[/tex]

Total energy used by the United States in the year 2000 [tex]E_{2000}=1.0*10^20[/tex]

Generally the equation of speed of rocket v mathematically given by

[tex]v=\frac{2d}{\triangle t}[/tex]

[tex]v=860ly/ \triangle t[/tex]

where

[tex]\triangle t=\frac{\triangle t'}{(\sqrt{1-860/ \triangle t)^2}}[/tex]

[tex]\triangle t=\frac{36}{(\sqrt{1-860/ \triangle t)^2}}[/tex]

[tex]\triangle t=\sqrt{(860)^2+(36)^2}[/tex]

[tex]\triangle t=860.7532[/tex]

Therefore

[tex]v=\frac{860ly}{ 860.7532}[/tex]

[tex]v=0.999124c[/tex]

b)

Generally the equation of the energy E required to attain prior speed mathematically given by

[tex]E=\frac{1}{\sqrt{1-(v/c)^2} }-1(20000kg)(3*10^8m/s)^2[/tex]

[tex]E=7.566*10^{22}[/tex]

c)Generally the equation of the energy [tex]E_a[/tex] required to accelerate the rocket mathematically given by

[tex]E_a=\frac{E}{E_{2000}}[/tex]

[tex]E_a=\frac{7.566*10^{22}}{1.0*10^{20}}[/tex]

[tex]E_a=760 times\ larger[/tex]

How did the projected storm track change from image A TO B TO C TO D

Answers

Link provided in other answer is a SCAM, don’t click on the link !!!!

The light waves transfer their oscillations and energy to other object in what way?

The frequency of the light waves physically causes the object to move
The energy of the light wave transfers to the electrons of the material which causes them to gain that energy
The wavelength of the light changes the velocity of the atoms in the material
The amplitude of the light will affect how much of it shines on the object

Answers

Answer: b the energy of light...

Explanation:

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