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o-na [289]
2 years ago
14

The H line in Calcium is normally at 396.9 nm. However, in a star's spectrum, it is measured at 398.1nm. How fast is the star mo

ving and is it moving towards the Earth or away from the Earth?
1- 904.3 km/s away from the Earth
2- 904.3 km/s towards the Earth
3- 907.0 km/s towards the Earth
4- 907.0 km/s away from the Earth
Physics
1 answer:
agasfer [191]2 years ago
3 0

As we know by Doppler's effect of light we have

\frac{\Delta \lambda}{\lambda} = \frac{v}{c}

here we will have

[tex}\frac{398.1 nm - 396.9 nm}{398.1 nm} = \frac{v}{c}[/tex]

here by solving above we have

3.01 \times 10^{-3} = \frac{v}{c}

here we have

v = 904.3 km/s

since wavelength is increased so we can say that it is moving away

so correct answer is

1- 904.3 km/s away from the Earth

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2 years ago
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The solution to your problem is as follows:


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21.56N*1.25m = 26.95J </span>


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An air-track glider undergoes a perfectly inelastic collision with an identical glider that is initially at rest. what fraction
DiKsa [7]
Refer to the diagram shown below.

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m*u = 2m*v
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The final KE is
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2 years ago
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A 1.00-kg duck is flying overhead at 1.50 m/s when a hunter fires straight up. The 0.010 0-kg bullet is moving 100 m/s when it h
lbvjy [14]

Answer:

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Explanation:

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1.01v=2.5

v=2.4752m/sec

7 0
2 years ago
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