The Sun is a star that is in a stable state called the main sequence.
Describe the evidence that suggests some stars are moving away from Earth.

Answers

Answer 1
Astronomers believe some stars are moving away from earth by measuring the extent to which their light is “stretched” into the red part of the color spectrum, representing the lower frequencies on that spectrum.

In short, stars moving away from earth are “red-shift”, while if they were moving towards the earth they would take on a “blue-shift”.

Related Questions

In terms of net charge, how does an electrically polarized object differ from an electrically charged object?.

Answers

Answer:

An electrically polarized object can carry no net charge

Example: charge Q at +x   and charge -Q at -x        for no net charge

An electrically charged object has a net charge on the object

why does the temperature remain constant at the boiling point of water when the internal energy is increasing?

Answers

The temperature remain constant at the boiling point of water when the internal energy is increasing because: all the heat energy provided is used up in changing the state of water from liquid to gaseous water vapour.

Meaning of Change in State

A Change in state can be defined as the process of moving from one matter form to another due to heat supplied or removed.

A change in state can happen in different forms of matter.

In conclusion, The temperature remain constant at the boiling point of water when the internal energy is increasing because: all the heat energy provided is used up in changing the state of water from liquid to gaseous water vapour.

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Physicists make their work easier by summarizing data in tables and graphs and by abbreviating quantities

Answers

Answer:

visual are used as a way for our brains to Kriti understand information which is the powerful tool is used for glass can show a large amount of data quickly in a way that it is to process with a bunch of numbers

Explanation:

graph and charts communicate information visually they can show pattern self scientist simply corrections and guess the point of experiment across quickly depended variable is y axis

An upward electric force of 10 N is exerted on a 3 C charge. Find the magnitude and direction of the electric field at the position of this charge. Group of answer choices Cannot be determined 30 N/C, upward 30 N/C, downward 3.33 N/C, downward 3.33 N/C, upward

Answers

The magnitude and direction of the electric field at the position of this charge.3.33 N/C upward

An electric field is the electric force per unit of charge. It is assumed that the field's direction corresponds to the direction in which a positive test charge would experience force. The electric field is directed radially inward toward a negative point charge and radially outward from a positive charge.

Value of force F given  = 10N

value of charge Q = 3 C

We know that E = F/Q

E = 10/3

= 3.33N

where charge is scalar quantity so the direction of force is the direction of electric field

Hence the magnitude and direction of the electric field at the position of this charge.3.33 N/C upward

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A 2.00 kg block hangs from a spring. A 300 g body hung below the block stretches the spring 2.00 cm farther. (a) What is the spring constant

Answers

The spring constant is 147 N/m

Given the mass of the block is 2.00 kg , the mass of the body is 300 g and the length of the spring is 2.00 cm

We need to find the spring constant

A spring is an object that can be deformed by a force and then return to its original shape after the force is removed.

The force required to stretch an elastic object such as a metal spring is directly proportional to the extension of the spring

We know that F = kx

300(9.8)= k (0.02)

k = 147.15 N/m

Rounding off to the nearest is 147N/m

The spring constant is 147N/m

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What is the measure of angle e? m∠e = ° what is the length of ef rounded to the nearest hundredth? ef ≈

Answers

The Measure of angle E is 55° and Length of the side EF is 12.49 units

The diagram is missing in the question and hence the diagram is shown below!!!

Given the triangle EDF with angle measures ∠D = 43° and ∠F = 82°.

As, we know, The sum of the measures of angles in a triangle is 180°.

So, we have,

∠E + ∠D + ∠F = 180°

i.e. ∠E + 43° + 82° = 180°

i.e. ∠E = 180° - 125°

i.e. ∠E = 55°

Thus, the measure of angle E is 55°.

Further we have

15/sin55 = EF / sin43

∴ EF =  15*sin43/sin55

∴EF = 10.23/0.189

EF = 12.49 units

Hence the length of side of EF is 12.49 units

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Please give the person above me brainliest!!!

✔ 55

✔ 12.49

A current of 2a flow through a bulb for 2.5 minutes determine the quantity of the charge that flows through the bulb

Answers

The quantity of the charge that flows through the bulb is 300 Coulombs.

What is charge flow:

The flow of charge is the process of supplying electric charge to an object or losing electric charge from an object.The flow of charge is also known as the Electric current.

Formula of current:

I = Q / t

Current is determined by the number of electrons passing through a cross-section in one second.

here,

current, I = 2 A

time, t = 2.5 minutes

t = 2.5* 60 = 150 seconds

substituting the values in formula,

I = Q / t

Q = I * t

Q = 2 * 150

Q = 300 coulombs

The quantity of the charge that flows through the bulb is 300 Coulombs.

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For conservative forces, force can be found as being the negative of the derivative of.

Answers

Answer:

Force is the negative derivative of potential:

V = G M / R       potential at distance R from mass M

F = dV / dR = - G M / R^2        force at distance R from mass M

Potential relays measure the back ________ developed across the ________ winding to operate the relay.

Answers

Potential relays measure the back emf developed across the start winding to operate the relay.

What is Potential:

the quantity determining the energy of mass in a gravitational field or of charge in an electric field.

Potential relays are used with single-phase capacitor, which need relatively high starting torque.

Their main function is to assist in starting the motor.

When power is applied to the coil, the contact(s) change position.

A relay with power applied to the coil is said to be energized.

Back EMF is the system in the coil of an electric motor that opposes the current flowing through the coil, when the armature rotates.

so here,

Potential relays measure the back emf developed across the start winding to operate the relay.

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A fluorescent light "hums" at
120 Hz. A bored grad student
hums at 118.4 Hz. What beat
frequency does he hear in his
head?
(Unit = Hz)
(This is on autobiographical problem buthe

Answers

The beat frequency he hears in his head will be 1.6 Hz

What is the frequency of the sound?

A sound pressure wave's frequency, also known as pitch, is the number of times it repeats itself every second.

The frequency of the sound is the inverse of the period. If the wavelength of a wave is short. The wave will indeed have a lower frequency. A longer wavelength denotes a lower frequency.

Given data;

The frequency at which the fluorescent light "hums",f=120 Hz

The frequency at which the bored grad student "hums",f'=118.4 Hz

The beat frequency he hears in his head is,fₐ=?

The beat frequency he hears in his head is found as;

fₐ = f-f'

fₐ = 120 - 118.4 Hz

fₐ = 1.6 Hz

Hence the beat frequency he hears in his head will be 1.6 Hz.

At 120 Hz, a fluorescent light "hums." At 118.4 Hz, a Ph.D. student who is bored hums. He hears 1.6 Hz as the rhythm frequency in his brain.

Hence the beat frequency he hears in his head will be 1.6 Hz

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what is specific latent heat mean in simple word?​

Answers

Answer:

Amount of energy required to change the 1kg of a substance without changing its temperature.

Using the side lengths of △pqr and △stu, which angle has a sine ratio of four-fifths? ∠p ∠q ∠t ∠u

Answers

∠p has a sine ratio of four-fifths.

The answer is option A.

Trigonometric Ratios are defined because the values of all the trigonometric features are based totally on the fee of the ratio of sides in a right-angled triangle. The ratios of sides of a right-angled triangle with recognition of any of its acute angles are referred to as the trigonometric ratios of that particular perspective.

The six trigonometric ratios are sine (sin), cosine (cos), tangent (tan), cotangent (cot), cosecant (cosec), and secant (sec).

In geometry, trigonometry is a department of mathematics that offers the sides and angles of a right-angled triangle. Therefore, trig ratios are evaluated with admire to aspects and angles.

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Answer: A

Explanation: Angle P

How can you use your experimental results to find where the electric field has the greatest intensity

Answers

Using the experimental result greatest electric fleld can be found in practical application.

According to the problem,

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The box is sitting on the floor of an elevator. The elevator is slowing down moving upward. The magnitude of the normal force on the box is:

Answers

Answer:

The magnitude of the normal force on the box is N= m*g + W

Explanation:

According to Newton's Second law and normal force.

The resultant of the forces acting on the person must be equal to the product between the mass and the acceleration a of the person itself.

so with the help of Newton's second law

we can write the equation for force:

F = ma

Since,

box is sitting on floor of an elevator.

there are two forces acting on this box:

W due to it's weight (downward) N due to the normal force of the floor against the body (upward).

So we can rewrite the previous equation as,

N - W = F

N - W = ma

hence,

N=m*a + W

this is the The magnitude of the normal force on the box.

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Two boys are playing with two different balls of masses m and 2 meter respectively. if first boy through vertically up and the second boy throws at an angle teta from vertical and balls remains same time in air what will be the ratio of height attend by the two balls

Answers

The ratio of the height attended by the object thrown upward to that thrown at some angle θ with the vertical is 1.  

Note: It is assumed that the mass of the first object is m and the mass of the second object is 2m. Also, the first object is thrown upward and the second object is thrown at some angle θ with the vertical.

Projectile motion: Any object that is thrown in the air is called a projectile and the motion described by it under gravity is called the projectile motion.  

If the air resistance is neglected, then the acceleration due to gravity g is the same for all objects irrespective of their masses. It is given that both objects remain in the air for the same time period. So first calculate the time period for the objects when they are in the air.

Time period of the first object: The first object is thrown in the air upwards so from the second kinematics equation,

h1=u1*t1-(1/2)*gt1^2

where h1 is the height, t1 is the time, and u1 is the initial velocity for the first object.

When the object is not in air h1=0, so

0=u1*t1-(1/2)*gt1^2

After solving the above quadratic equation, the values of t1 obtained are t1=0 which represents the initial time, and t1=2u1/g which represents the time period. So the time period of the first object is,

t1=2u1/g

Time period of the second object: The second object is thrown at some angle θ with the vertical as shown in the diagram. From the diagram, the initial velocity along the vertical direction is,

u2=uocos(θ)

where uo is the initial velocity and u2 is the initial velocity along the vertical direction.

From the second kinematic equation,

h2=u2*t2-(1/2)*gt2^2

where h2 is the height, t2 is the time, and u2 is the initial velocity for the second object along the vertical direction.

When the object is not in air h2=0, so using u2=uocos(θ),

0=uocos(θ)*t2-(1/2)*gt2^2

After solving the above quadratic equation, the values of t2 obtained are t2=0 which represents initial time, and t2=2uocos(θ)/g which represents  the time period. So the time period of the second object is,

t2=2uocos(θ)/g

Given that the time period is the same for both cases,

t1=t2

2u1/g=2uocos(θ)/g

u1=uo cos(θ)

Calculation of the ratio of the height of the object:

The maximum height is attained when the time of the object in the air is half of the total time period. At maximum height, velocity is zero.

From the third equation of motion.

v^2=u^2-2gh

h=u^2/2g

where h is the height and u is the initial velocity of an object.

Using it and u1=uo cos(θ) and u2=uo cos(θ), the ratio of h1 and h2 is,

h1/h2=  u1^2/2g÷u2^2/2g

h1/h2=(uo cos(θ))^2/(uo cos(θ))^2

h1/h2=1

The ratio of their height will be 1.

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A bowling ball rolls down a lane and hits a bowling pin. Which statement below is true about the forces exerted during the impact?
Group of answer choices

a. The force that they exert on each other has the same magnitude.

b. The bowling pin exerts a larger force on the ball than the ball does on the pin.

c. One of the two forces is larger, but which is larger cannot be determined unless more information is provided.

d. The bowling ball exerts a larger force on the pin than the pin does on the ball.

Answers

The statement that is true about the forces exerted during the impact is that force that they exert on each other has the same magnitude (option A).

What is Newton's third law of motion?

Newton's third law of motion states that to every action (force applied) there is an equal but opposite reaction (equal force applied in the opposite direction).

This law suggests that when a bowling ball rolls down a lane and hits a bowling pin. The bowling pin applies an equal force but in an opposite direction.

Therefore, the statement that is true about the forces exerted during the impact is that force that they exert on each other has the same magnitude.

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The Renaissance astronomer who wrote the pioneering book that suggested the Earth probably orbits the Sun (instead of the other way around) was:

Answers

Nicolaus Copernicus wrote the pioneering book that suggested the Earth probably orbits the Sun (instead of the other way around).

Who was Nicolaus Copernicus ?

The father of modern astronomy is Polish astronomer by the name of Nicolaus Copernicus. He was the first contemporary scientist from Europe to put forth the Heliocentric Theory of the universe, which holds that Earth and other planets rotate around the sun.

By reading other astronomers' writings and making his own observations, Copernicus established his heliocentrism theory. He noted that heliocentrism provided a much more comprehensive explanation for the motions of the planets. Nicolaus Copernicus created his own heliocentric planetary system astronomical model. He published his results in the Commentariolus somewhere about 1514.

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A conducting shell has total extra charge . At some time, you place a charge at the center of the shell. How the charges distribute themselves

Answers

Answer:

There can be no net charge inside the conductor, and the charge must reside uniformly on the outside surface of the sphere.

what is conducting shell?

When there is charge present only on the surface, the sphere is called conducting shell.

Here, A conducting shell has total extra charge.

Gauss’s Law is defined as:

The flux through a closed surface is equal to the total charge enclosed within the closed surface divided by the permittivity of vacuum.

The electric field of conducting sphere of uniform charge:

E = k*Q/r^2

From the Gauss law we can say that,  

There can be no net charge inside the conductor, and the charge must reside uniformly on the outside surface of the sphere.

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Where does the first stage of cellular respiration occur?
O w
O x
OY
O Z

Answers

It occurs in the Cytoplasm of your cells

short for Cytoplasm is CYT

What was a surprise to astronomers when they carefully examined Neptune with the Hubble Space Telescope in 1994

Answers

A surprise to astronomers when they carefully examined Neptune with the Hubble Space Telescope in 1994 was that the Great Dark Spot had disappeared.

What is Neptune?

Neptune refers to the the eighth planet from the distance to the Sun, which was carefully observed with the Hubble Telescope in 1994.

Neptune had a Great Dark Spot that had disappeared in 1994, which represented a spectacular and giant storm.

In conclusion, a surprise when scientists examined Neptune with Hubble telescope was that the Great Dark Spot had disappeared.

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On a calm day with no wind, you can run a 1500-m race at a velocity of 4.0 m/s. If you run the same race on a day when you have a constant headwind that slows your speed by 2.0 m/s, how much time would it take you to finish the race

Answers

Answer:

The required time is 750 s.

Explanation:

The velocity of the man gets slowed by 2.0 m/s when the wind is blowing.

Therefore the speed of the man on the day of wind is (4.0-2.0)=2.0 m/s.

The time, speed and distance are related by the equation,

t=v/d

Given v= 2 m/s and d=1500 m.

The required time is,

t=1500/2

t=750 s

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Consider two planets in space that gravitationally attract each other. If the masses of both planets are doubled, and the distance between them is also doubled, then the force between them is

Answers

The force between the planets will not change after doubling the masses of the planets and distance between them.

To find the answer, we need to know about the gravitational force of attraction.

What's the gravitational force attraction?According to Newton's gravitational law, the force between two objects is directly proportional to the product of their masses and inversely propertional to the square of the distance between them.Mathematically, Gravitational force= GMm/r². G is the gravitational constant.What is the gravitational force between two planets when their masses and distance between them are doubled?Then masses are 2M and 2m. Distance is 2r.So gravitational force= G×2M×2m/(2r)²

= GMm/r²

Thus, we can conclude that the gravitational force will not change of the masses are doubled and the separation is also doubled between the planets.

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Gabrielle has just upgraded her oil-burning furnace. Her new furnace takes cool air from outside and passes it through the heat source using a fan or blower. What type of furnace has she upgraded to

Answers

Gabrielle has just upgraded her oil-burning furnace to a  Forced air system.

What is  furnace?

A furnace is a place where combustion takes place. In a furnace, it is normal to burn a carbonaceous material and produce energy in the process.

The type of furnace that  takes cool air from outside and passes it through the heat source using a fan or blower is a  Forced air system. Hence, Gabrielle has just upgraded her oil-burning furnace to a  Forced air system.

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Higher-pitched sounds have shorter wavelengths.

True or false

Answers

Answer:

The answer is True

Explanation:

I hope it helps

Answer:

it's true

Explanation:

High–pitched sounds have short wavelengths, which means that the peaks are close together. Low–pitched sounds have longer wavelengths, so the peaks are more spread out.

What constant acceleration is required to increase the speed of a car from 26 mi/h to 51 mi/h in 5 seconds

Answers

2.25 m/s² of acceleration is required to increase the speed of a car from 26 mi/h to 51 mi/h in 5 seconds.

To find the answer, we need to know about the acceleration.

What is acceleration?Acceleration is given as the ratio of velocity to time.Mathematically, acceleration= velocity/time.What is the acceleration required to increase the speed of a car from 26 mi/h to 51 mi/h in 5 seconds?Here change in velocity of the car is 51-26= 25 mi/h. As 1 mi/h = 0.45 m/s. So 25mi/h = 11.25 m/s.Acceleration= (11.25m/s)/5s = 2.25 m/s².

Thus, we can conclude that the constant acceleration is 2.25 m/s².

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The magnetic field at the center of two concentric current loops is zero. The smaller loop has a radius of 0.01 m and a current of 10.0 A. The larger current loop carries a current of 29.0 A. What is the radius of the larger loop

Answers

Answer:

B = μ I / (2 * R)     magnetic field at center of current carrying loop

I1 / R1 = I2 / R2        and we want to know R2

R2 = I2 / I1 * R1 = 29 / 10 * 01 = .029 m

A 66.0 kg diver is 3.10 m above the water, falling at speed of 6.10 m/s. Calculate her kinetic energy as she hits the water. (Neglect air friction)

Answers

Kinetic energy as she hits the water is 3300 joule.

To find the answer, we need to know about the Newton's equation of motion.

What's the Newton's equation of motion to determine the final velocity?The final velocity is determined as

V²=U²+2aS

V= final velocity, U= initial velocity, a= acceleration and S= distanceWhat's the final velocity of the driver falling from 3.10m with initial velocity of 6.10m/s?Here, a= 9.8m/s², U= 6.10m/s and S= 3.10mSo, V²= 6.1²+2×9.8×3.10= 98 V= √98= 10m/sWhat's the kinetic energy of the driver when touches the water?

Kinetic energy= 1/2×mass×velocity²

= 1/2 × 66 × 10²

= 3300J

Thus, we can conclude that the kinetic energy of the driver is 3300 Joule.

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An unstoppable object is heading right toward an unmovable object. What's going to happen?

Answers

Answer:

In my opinion the unstoppable object will hit the unmovable object and stop but the wheels will still be rolling and trying to move but can't.

Hope this helps.Good luck ✅.

a person complete a 100m race in 11s. He accelerates for the first two second and then maintains the velocity till the end. what is the maximum velocity reached

Answers

The maximum velocity reached by the person is determined as 11.1 m/s.

Area under velocity - time graph

The area under the velocity time graph is the total displacement of the person.

Total Area = area of triangle formed during first 2 seconds + area of rectangle during the last 8 seconds

100 = ¹/₂(2v) + v(11 - 2)

where;

v is the maximum velocity

100 = v + 8v

100 = 9v

v = 100/9

v = 11. 1 m/s

Thus, the maximum velocity reached by the person is determined as 11.1 m/s.

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An uncharged metal rod brought close to but not touching the cap of a charged electroscope caused decrease in the divergence of the leaf. Explain this observation.

Answers

-ItzKenzo

-CuteSiKenzo(Oo cute)

Alam kung wala kang pake tángina mo!!

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