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2 years ago

How do scientists use the doppler effect to understand the universe?

Physics

2 answers:

Contact [7]2 years ago

8 0

Answer: The correct answer is A.

The correct answer is C.

Explanation:

Doppler effect is the phenomenon in which there is an apparent change in the frequency of the wave when there is a relative motion between the observer and the source.

Scientists use the Doppler effect to understand the universe by determining the motion of the object.

Therefore, the correct answer is A.

Light changes as the object in space (such as star) moves away from us then the light is shifted to red end. In this case, the light is shifted to longer wavelength.

Light changes as the object in space (such as star) moves towards us then the light is shifted to blue end. In this case, the light is shifted to shorter wavelength.

In the given problem, the when the stars are moving towards each other then the blue shift in the light will occur.

Therefore, the correct option is C.

Nadusha1986 [10]2 years ago

6 0

For the First answer, It would be "A"

The for the next one the answer is "C"

I hope this helps. :)

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A sample of ascorbic acid (vitamin C) is synthesized in the laboratory. It contains 1.50 g of carbon and 2.00 g of oxygen. Anoth

Karo-lina-s [1.5K]

Answer:

8.467 gm

Explanation:

The law governing this problem is "The Law of Constant Composition "

As per this law, all compounds irrespective of their origin and source have the same composition and properties in their purest form

It is a simple proportion and ratio related problem.

1.50 grams of carbon require 2.0 grams of oxygen

1.0 grams of carbon will require oxygen

= $\frac{2}{1.5}$

6.35 grams of carbon will require oxygen

$\frac{2}{1.5}\times6.35$ = 8.4666\\= 8.467

6 0

2 years ago

Calculate the standard electrode potential difference (e°) of the daniell cell (at 1 bar) if temperature is 473.15 k.

anzhelika [568]

Missing data in the text of the exercise: The molar concentration of Zinc is 10 times the molar concentration of copper.

Solution:

1) First of all, let's calculate the standard electrode potential difference at standard temperature. This is given by:
$E^0=E_{cat}^0-E_{an}^0$
where $E_{cat}^0$ is the standard potential at the cathode, while $E_{an}^0$ is the standard potential at the anode. For a Daniel Cell, at the cathode we have copper: $E_{Cu}^0=+0.34 V$ , while at the anode we have zinc: $E_{Zn}^0=-0.76 V$ . Therefore, at standard temperature the electrode potential difference of the Daniel Cell is
$E^0=+0.34 V-(-0.76 V)=+1.1 V$

2) To calculate $E^0$ at any temperature T, we should use Nerst equation:
$E^0(T)=E^0- \frac{R T}{z F} \ln \frac{[Zn]}{[Cu]}$
where
$R=8.31 J/(K mol)$
$T=473.15 K$ is the temperature in our problem
$z=2$ is the number of electrons transferred in the cell's reaction
$F=9.65\cdot 10^4 C/mol$ is the Faraday's constant
$[Zn]$ and $[Cu]$ are the molar concentrations of zinc and in copper, and in our problem we have $[Zn]=10[Cu]$ .
Using all these data inside the equation, and using $E^0=+1.1 V$ , in the end we find:
$E^0(T)=E^0- \frac{R T}{z F} \ln \frac{[Zn]}{[Cu]}=+1.053 V$

8 0

2 years ago

It is important for physicians to be _____ patient use of alternative therapies.

V125BC [204]

It is important for physicians to be Respectful of patient use of alternative therapies

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2 years ago

Explain how astronomers might use spectroscopy to determine the composition and temperature of a star.

Damm [24]

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4 0

3 years ago

A good sign that cardiovascular exercise is occurring is that you _____.

grigory [225]

Are breathing hard. This is because cardiovascular exercise makes the heart beat faster which in turn creates a need for more air.

4 0

2 years ago

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