What does the color of a star indicate

Answers

Answer 1

Answer:

Its temperature

Explanation:

Answer 2

Answer:

The stars age

Explanation:

As stars age, they run out of hydrogen to burn, decreasing the amount of energy they give off. So the younger stars can look bluer while older ones look more red.

Hope this helps :3


Related Questions

State the forces acting on an object that is stationary/moving. Explain how acceleration changes when the same object is kicked with a great force and a small force. Describe the difference in the movement if the initial object now weighs 50 lbs and is acted on by a small force and a large force.​

Answers

Answer:

it all is force I the barly kick you then it won't do that much date but If the full force kick you then it might hurt.

Explanation:

i hope this helps


If you apply a net force of 3 N on 100g -box, what is the acceleration of
the box? *
30 m/s/s
20 m/s/s
10 m/s/s
5 m/s/s

Answers

Answer:

I believe the correct answer is 30m/s/s

How many significant figures? 53,598 m/sec

Answers

Answer:

This has 5 significant figures.

I NEED HELP SOLVING THIS!!!!!!!!!!!!

Jose Altuve hits a fastball with a velocity of 49.1 m/s (109.9 mph) at an angle of 22º. If left field is 96 m (315 ft) away, will this be a home run?

Answers

Answer:

Yes

Explanation:

The given parameters are;

The speed with which the fastball is hit, u = 49.1 m/s (109.9 mph)

The angle in which the fastball is hit, θ = 22°

The distance of the field = 96 m (315 ft)

The range of the projectile motion of the fastball is given by the following formula

[tex]Range = \dfrac{u^2 \times sin(2\cdot \theta)}{g}[/tex]

Where;

g = The acceleration due to gravity = 9.81 m/s², we have;

[tex]Range = \dfrac{49.1^2 \times sin(2\times22^{\circ})}{9.81} \approx 170.71 \ m[/tex]

Yes, given that the ball's range is larger than the extent of the field, the batter is able to safely reach home.

Your mother has called you on your cell phone and asked you to pick up a few items at the grocery store on your way home. As you heard your mother state each item, which process transferred this information from your sensory memory to your short-term memory so you could jot each grocery item down?

Answers

Answer:

Encoding

Explanation:

Encoding is the initial learning of information. Encoding is the process of passing new information coming from sensory input  into our brain so that it can be easily retrievable. In a nutshell, it is the sum total of the processes by which external information such as the list of items your mother asked you to pick up at the grocery store to be converted into a manner that can be stored within the brain and recalled later from long-term memory.

Encoding has to do with transferring external stimuli into short term and subsequently long-term memory.

PLEASE HELP

Which object has the least average speed?

A. object A
B. object B
C. object C
D. object D

Answers

Answer:

D

Explanation:

I could be wrong, But I'm pretty sure it's D

The data table shows how the amplitude of a mechanical wave varies with
the energy it carries. Analyze the data to identify the mathematical
relationship between amplitude and energy. Use your equation to find the
energy if the amplitude is 6 units.
Amplitude
Energy
1 unit
2 units
2 units
8 units
3 units
18 units
4 units
32 units

Answers

Answer:

162

Explanation:

When the amplitude of the wave is 8 units, the corresponding energy of the wave is 128 units. Therefore, option C is correct.

What do you mean by an amplitude ?

The term amplitude is defined as the maximum distance moved by a point on a vibrating body or wave calculated from its equilibrium position.

We have given,

first amplitude, A = 1, corresponding energy = 2

second amplitude, A = 2, corresponding energy = 8

The energy of a string at  a given amplitude is calculated as follows;

E ∝ A²

Energy varies as the square of the change in amplitude.

If amplitude of one has energy of two

Amplitude of 2 (double of 1)

= ( 2 x 2 ) = 4 x 2

= 8  4 times the energy at amplitude of 1.

Then for 8 units of amplitude change

8 x 8 = 64 x 2

= 128  

Thus, When the amplitude of the wave is 8 units, the corresponding energy of the wave is 128 units, option C is correct.

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Your question is incomplete, most probably your question was

The data table shows how the amplitude of a mechanical wave varies with the energy it carries. Analyze the data to identify the mathematical relationship between amplitude and energy. Use your equation to find the energy if the amplitude is 8 units.

Amplitude

1

2

3

4

energy

2

8

18

32

A.66 units

B. 108 units

C. 128 units

D. 88 units ​

a train starting from a distance of velocity of 90 km.h
-1 in 10 minutes assuming that the acceleration is uniform find the acceleration and the distance travelled by the train for attending the velocity​

Answers

To make this problem solvable and you can get the help you need, I'll complete and arrange some data.

Answer:

Acceleration: [tex]0.0417\ m/s^2[/tex], Distance=7,500 m

Explanation:

Uniform Acceleration Motion

It's a type of motion in which the velocity of an object changes uniformly over time.

Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, the following relation applies:

[tex]v_f=v_o+at\qquad\qquad [1][/tex]

The distance traveled by the object is given by:

[tex]\displaystyle x=v_o.t+\frac{a.t^2}{2}\qquad\qquad [2][/tex]

Using the equation [1] we can solve for a:

[tex]\displaystyle a=\frac{v_f-v_o}{t}\qquad\qquad [3][/tex]

The problem will be rewritten as follows:

A train starting from rest reaches a velocity of 90 km/h in 10 minutes. Assuming that the acceleration is uniform, find the acceleration and the distance traveled by the train for attending the velocity​.

Let's take the relevant data:

vo=0

vf=90 Km/h*1000/3600 = 25 m/s

t = 10 minutes = 10*60 = 600  seconds

Now compute the acceleration by using [3]:

[tex]\displaystyle a=\frac{25-0}{600}=0.0417[/tex]

[tex]a=0.0417\ m/s^2[/tex]

Finally, compute the distance:

[tex]\displaystyle x=0*600+\frac{0.0417\cdot 600^2}{2}[/tex]

[tex]x=7,500\ m[/tex]

Note: We used the value of the acceleration with more precision than shown.

Acceleration: [tex]\mathbf{0.0417\ m/s^2}[/tex], Distance=7,500 m

Invasive species often display a wave of advance as they colonize new areas. Mathematical models based on random dispersal and reproduction have demonstrated that the speed with which such waves move is given by the expression 2 Dr , where r is the reproductive rate of individuals and D is a parameter quantifying dispersal. Calculate v'(r), the derivative of the wave speed with respect to the reproductive rate r.

Answers

Complete Question

The complete question is shown on the first uploaded image

Answer:

The derivative is  [tex]v(r)' =  \sqrt{\frac{D}{r} }[/tex]

The correct option is option 1

Explanation:

From  the question we are told that

   The equation of the speed of the wave of invasion is  [tex]v(r)  = 2 \sqrt{Dr}[/tex]

=>  [tex]v(r)  = 2 (Dr)^{\frac{1}{2} }[/tex]

=>  [tex]v(r)  = 2 * D^{\frac{1}{2} } r^{\frac{1}{2} }[/tex]

    Here r is the reproductive rate and the D is the parameter qualifying dispersal

Generally the derivative of this speed is mathematically represented as

         [tex]v(r)' = \frac{2}{2}  *  D^{\frac{1}{2} } *  r^{-\frac{1}{2} }[/tex]

=>     [tex]v(r)' =  \sqrt{\frac{D}{r} }[/tex]  

This derivative of the speed represents the rate of change of the invasive speed with respect to the the reproductive rate of an individual

Acceleration is the rate of change in the speed of an object. To determine the rate of acceleration, you use the formula below. The units for acceleration are meters per second per second or m/s2.

Answers

Explanation:

Acceleration is the rate of change in the speed of an object. If initial and final speed are v₁ and v₂. It changes speed in time t. Its formula is given by :

[tex]a=\dfrac{v_2-v_1}{t}[/tex]

The problem is "A skater increases her velocity from 2.0 m/s to 10.0 m/s in 3.0 seconds. What is the skater’s acceleration? "

In this problem,

v₁ = 2 , v₂ = 10 m/s and t = 3 s

Acceleration of the object,

[tex]a=\dfrac{10-2}{3}\\\\a=2.67\ m/s^2[/tex]

So, the acceleration of the skater is [tex]2.67\ m/s^2[/tex].

In the desert air, sound travels at 358 meters per second (m/s). In the polar air, sound travels at 330 meters per
second (m/s). What can you conclude from this information?
A - The speed of sound is constant.
B - Sound waves travel fastest in a vacuum.
C-The temperature of the air affects the speed of sound.
D-Sound waves travel at the same speed everywhere on Earth.
Please provide your answer below using CER
1. Claim: What is your choice for the correct answer?
2. Evidence: What evidence did you observe from the test-like question that made you decide on your answer?
3. Reasoning: Provide an elaboration on your evidence, possible prior knowledge about your claim.

Answers

Answer:

The correct option is;

C. The temperature of the air affects the speed of sound

Explanation:

The information given are;

The speed with which sound travels in the desert air = 358 m/s

The speed with which sound travels in the polar air = 330 m/s

The major difference between the desert air and the polar air is that the temperature of the desert air is hotter than the temperature of the air in the polar region. Therefore the speed of sound is affected by the air temperature.

The equation that gives the relationship of the speed of sound in air, [tex]v_{air}[/tex], to temperature is presented as follows;

[tex]v_{air} = 331\frac{m}{s} \times \sqrt{\dfrac{T_K}{273 K} } = 331\frac{m}{s} \times \sqrt{1 + \dfrac{T_{^{\circ}C}}{273 ^{\circ} C} }[/tex]

Which shows that the speed of sound in air, [tex]v_{air}[/tex], rises as the temperature of the air rises.

Where;

[tex]T_{^{\circ}C}[/tex] = The temperature of the air in degrees Celsius

[tex]T_K[/tex] = The temperature of the air in degrees Kelvin.

convert 9.2 km to m​

Answers

Answer:

9,200 m

Explanation:

1 kilometer = 1000 meters so if there is 9 kilometers then it is 9000 meters, then .2 kilometer is equal to 200 meters. Add the numbers together to get 9,200 meters

An object is moving back and forth on the x-axis according to the equation x(t) = 3sin(20πt), t> 0, where x(t) is measured in cm and t in seconds. Give decimal answers below. (a) How many complete back-and-forth motions (from the origin to the right, back to the origin, to the left and finally back to the origin) does the object make in one second? (b) What is t the first time that the object is at its farthest right? (c) At the time found in part (b), what is the object's velocity? (d) At the time found in part (b), what is the object's acceleration?

Answers

Answer:

a.) 10Hz

b.) 0.1 s

c.) 187.4 m/s

d.) -412.6 m/s^2

Explanation:

Given that an object is moving back and forth on the x-axis according to the equation x(t) = 3sin(20πt), t> 0, where x(t) is measured in cm and t in seconds. Give decimal answers below.

(a) How many complete back-and-forth motions (from the origin to the right, back to the origin, to the left and finally back to the origin) does the object make in one second?

from the equation given,  the angular speed w = 20π

but w = 2πf

where f = frequency.

substitute w for 20π

20π = 2πf

f = 20π/2π

f = 10 Hz

(b) What is t the first time that the object is at its farthest right?

since F = 1/T

T = 1 / f

T = 1/10

T = 0.1 s

Therefore, the t of  first time that the object is at its farthest right is 0.1 s

(c) At the time found in part (b), what is the object's velocity?

The velocity can be found by differentiating the equation;

x(t) = 3sin(20πt)

dx/dt = 60πcos(20πt)

where dx/dt  = velocity V

V = 60πcos(20π * 0.1)

V = 187.4 m/s

(d) At the time found in part (b), what is the object's acceleration?

to get the acceleration, differentiate equation  V = 60πcos(20πt)

dv/dt = -1200πSin(20πt)

dv/dt = acceleration a

a = -1200πSin(20πt)

substitute t into the equation

a = -1200πSin(20π * 0.1)

a = - 412.6 m/s^2

The type of motion the object undergoes that consist of a back-and-forth

movement that is repetitive is a simple harmonic motion.

The correct responses are;

(a) Number of complete back-and-forth motions per second is 10(b) The first time is after 0.025 seconds(c) Velocity is 0(d) Acceleration is approximately -11843.53 m/s²

Reasons:

The equation that represents the motion of the object is x(t) = 3·sin(20·π·t)

Where;

t ≥ 0

x(t) is in cm, and t is in seconds.

(a) The general sine function is y = A·sin(B·(t - C) + D

[tex]\mathrm{The \ period \ P} = \dfrac{2 \cdot \pi}{B}[/tex]

By comparison, we have;

B = 20·π

Therefore;

[tex]P = \dfrac{2 \cdot \pi}{20 \cdot \pi} = \dfrac{1}{10} = 0.1[/tex]

The period, which is the time to complete one cycle = 0.1 seconds

The number of cycle completed per second, is the frequency, f

[tex]f = \dfrac{1}{P} = \dfrac{1}{0.1} = 10[/tex]

f = 10 Hz = 10 cycles

The number of cycle completed per second is f = 10 cycles

(b) When the object is at the farthest right, we have;

sin(20·π·t) = Maximum = 1

[tex]\mathbf{sin\left(\dfrac{\pi}{2}\right)} = 1[/tex]

Therefore,

[tex]20 \cdot \pi \cdot t = \dfrac{\pi}{2}[/tex]

[tex]t = \dfrac{\pi}{20 \cdot \pi \cdot 2} = \dfrac{1}{40} = 0.025[/tex]

The first time it is at the farthest right is t = 0.025 seconds after start

(c) [tex]\mathrm{Velocity, \ v, \ is \ given \ by \ v = \dfrac{dx(t)}{dt}}[/tex]

Therefore;

[tex]v = \dfrac{dx(t)}{dt} = \dfrac{dx(t)}{dt} \left(3 \cdot sin \left(20 \cdot \pi \cdot t \right) = 60\cdot \pi \cdot cos \left(20 \cdot \pi \cdot t \right)[/tex]

At t = 0.25 seconds, we have;

[tex]v = \dfrac{dx(t)}{dt} = 60\cdot \pi \cdot cos \left(20 \times \pi \times 0.025 \right) = 0[/tex]

The velocity of the object at the t = 0.025 seconds is v(t) = 0

(d) Acceleration, a, is given by [tex]a = \dfrac{dv(t)}{dt}[/tex]

Therefore;

[tex]a = \dfrac{dv(t)}{dt} = \dfrac{d}{dt} \left( 60\cdot \pi \cdot cos \left(20 \times \pi \times t\right) \right) =-1200 \cdot \pi ^2 \cdot sin(20 \cdot t \cdot \pi)[/tex]

a = -1200·π²·sin(20·t·π)

∴ a = -1200×π²×sin(20×0.025×π)

sin(20×0.025×π) = 1

∴ a = -1200×π²×1 ≈ -11843.53

At the time found in part b the acceleration of the object, a ≈ -11843.53 m/s²

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If the Mass Number is the sum of the protons and neutrons in an atom, what is
the mass number of

Answers

Answer:

It's 31

Explanation:

add 15 and 16

To decorate for a party, Simon needs 1,850 centimeters of colorful streamers. If the ratio of meters to centimeters is 1 : 100, how many meters of streamers does he require?

A.
18,500 meters
B.
185 meters
C.
18.5 meters
D.
1.85 meters

Answers

C because 1,850 divided by 100 is 18.50 but since zeros do not matter in decimals ( unless it is money ) we can removes the zero making it 18.5 meters

A student is given a 5.4 g mineral sample. She determines that the volume of her sample is 2 cm3. What is the density of her mineral

Answers

Answer:

6.7

Explanation:

13. A baseball pitcher throws a fastball at a speed of 46m/s. The
acceleration occurs as the pitcher holds the ball in his hand and moves it
through an almost straight line distance of 3.5 m. Calculate the
acceleration, assume it is constant and uniform. (Answer in 3 sig figs and
do not include units) *

Answers

Answer: Approximately 302 m/s^2

================================================

Work Shown:

s = starting velocity = 0

f = final velocity  = 46

d = distance = 3.5

a = acceleration = unknown (we're solving for this)

[tex]f^2 = s^2 + 2a*d \ \ \text{ ..... one of the kinematics equations}\\\\46^2 = 0^2 + 2a*3.5\\\\2116 = 7a\\\\7a = 2116\\\\a = \frac{2116}{7}\\\\a \approx 302.28571\\\\a \approx 302[/tex]

The acceleration to three sig figs is roughly 302 m/s^2

The acceleration is so large because the ball's final velocity is incredibly fast in such a short amount of time.

what are some solutions to global temperature changes?
help asap​

Answers

Answer:

Power your home with renewable energy.

Weatherize, weatherize, weatherize.

Invest in energy-efficient appliances.

Reduce water waste.

Actually eat the food you buy—and make less of it meat.

Explanation:

Describe effect of artificial selection on the process of evolution

Answers

Answer: The process is called artificial selection because people (instead of nature) select which organisms get to reproduce.

Explanation: This is evolution through artificial selection and the characteristics to reproduce, causing the evolution of farm stock.

dimensional formula of energy​

Answers

Answer:

[M L2 T-2]

Explanation:

hope this is what you're looking for.

[M L2 T2] SI Symbol: J

define the word prism

Answers

Answer:

a polyhedron with two polygonal faces lying in parallel planes and with the other faces parallelograms

. Exercises that specifically prepare the muscles for active movements

Answers

Answer:

Dynamic Stretching

Explanation:

Dynamic Stretching: Dynamic stretches are controlled movements that prepare your muscles, ligaments and other soft tissues for performance and safety.

Answer:

Stretching such as toe touches

Forces may cause an object to change ____ if it is unable to move

Answers

Answer:

Motion

Acceleration is the change of velocity per unit time, so if there is no force, all we know is that the acceleration is zero. Therefore, the velocity is not changing. If the object was already moving, then it will just keep moving. So, the object can be moving even when there is no force applied to it.

Forces may cause an object to change its state if it is unable to move. The force make the object to move from its state of rest.

What is force?

Force is an external agent acting on an object to deform it or to change it state of rest or motion. There are various kinds of forces such as gravitational force, nuclear force, magnetic force, frictional force etc.

Force is a vector quantity thus, it is characterised by its magnitude and direction. According to Newton's first law of motion, an object will continue in its state or motion or rest until an external force acts on it.

Therefore, force changes the state of an object. Force is dependant on the mass of the object. Greater the mass, greater will be the force required to move the object from stationary to stop it from motion.

According to second law of motion, force is the product of mass and acceleration of the object. Hence, force accelerates the body and a change in force changes the acceleration of the object.

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Please help A.S.A.P
If the bands in an igneous rock are dark. What kind of magma was present when it was formed?

Answers

Answer:

The magma, molten rock under the surface, and lava (molten rock on the surface) harden into igneous rock. The igneous rock then breaks apart over time through the process of weathering.

Explanation:

PLEASE HURRY!

Zach listed the process of how laser beams are produced with crystals.

A flashlamp pumps energy through the crystal.
Atoms in the crystal absorb and then release some of the energy as light.
Light bounces off mirrors and occasionally bounces off crystal atoms, increasing in energy.
Some light escapes the tube through the highly reflective mirror, forming a concentrated beam.

Which best describes Zach’s error?

The crystal pumps energy through the flashlamp; the flashlamp does not pump energy through the crystal.
The atoms in the crystal do not release energy; they only absorb energy.
Light does not bounce off mirrors; it focuses through glass lenses.
Light escapes through the partially reflective mirror, not the highly reflective mirror.

Answers

The crystal pumps energy through the flashlamp; the flashlamp does not pump energy through the crystal best describes Zach’s error.

What is a laser?

A device that uses stimulated emission of photons from excited atoms or molecules to produce a strong beam of coherent monochromatic light is a laser.

When electrons in optical materials like glass, crystal, or gas absorb energy from an electrical current or light, a laser is formed.

The increased energy excites the electrons, causing them to migrate from a lower-energy orbit around the nucleus to a higher-energy orbit.

The crystal pumps energy through the flashlamp; the flashlamp does not pump energy through the crystal. This statement is incorrect.

Hence Option A best describes Zach’s error.

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Answer:

D. Light escapes through the partially reflective mirror, not the highly reflective mirror.

Explanation:

edge 2022, I took the test.

A car moved 40 km north and 90 km south. What is the displacement of the car?
A. 50 km south
B. 50 km north
C. 10 km east​

Answers

Answer:

A. 50 km south

Explanation:

hope this helps!

which refers to the distance between two crests or two troughs on a transverse wave?
wavelength
amplitude
frequency
hertz

Answers

Answer:

wavelength

Explanation:

the definition of wavelength is the distance from one Crest to the next crest,or one trough to the next trough

The phenomenon that refers to the distance between two crests or two troughs on a transverse wave is wavelength.

What is wavelength?

Wavelength is simply defined as the distance between successive crests of a wave, particularly in a sound.

In conclusion, wavelength refers to a traveling particle.

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Can someone please help me on this?

Answers

Answer:

80

Explanation:

The two objects have different masses, the more massive object pulls with a greater force. TRUE OR FALSE?

Answers

Answer:

on earth yes, but in space no because there is no gravity

Explanation:

plz can i have some points

The force exerted by an object depends on the mass of the object. Greater mass results in greater force. Hence, the statement is true.

What is force?

Force is an external agent acts on a body to change the substance from the state of rest or motion. There are various kinds of force such as nuclear force, magnetic force, frictional force etc.

According to Newton's law of motion force in a moving body is the product of its mass and acceleration. Hence, force is directly proportional to mass and acceleration and an increase in these quantities will increase the force exerted by the body.

Thus, greater force is needed to a move a body with greater mass. If two objects of different masses exerts force each other, the greater force will be exerted by the massive body.

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How many layers of data can a DVD store?
3
2
4
1
1

Answers

Answer:

Capacidad de almacenamiento ofrecida por los DVD

Hay que mencionar que es posible conseguir DVD de una o dos capas. Los DVD que cuentan con una capa son capaces de almacenar aproximadamente 4.7GB de datos, mientras que los de doble capa ofrecen la posibilidad de almacenar alrededor de 8.5GB

Explanation:

Answer:

4 layers

Explanation:

i took the quiz

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