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MrRa [10]
3 years ago
12

A graduate student has done a careful analysis of the spectrum of a star. While she has found lines from many elements, there wa

s not a trace of the element helium in the spectra she has been analyzing. From this she can now conclude:_______
Physics
1 answer:
disa [49]3 years ago
7 0

Explanation:

The lines in the spectra of star is due to absorption of light emitted by star by different elements  present in atmosphere of the star .

If some element is present in the outer atmosphere of he star , it will absorb a particular portion of light , for which there will be black line in the spectrum .

These are called Fraunhoffer's lines .

Now there is no such line at the place of Helium in the light spectrum . This means that Helium element is not present in the outer atmosphere of the star.

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A single brick falls with acceleration g. The reason a double brick falls with the same acceleration is
LekaFEV [45]

The reason is because the force due to the acceleration from gravity is constant. It's the same as the typical "dropping a bowling ball and feather (with no air resistance) at the same time". Gravity acts on all object with the same acceleration regardless of physical properties.

5 0
3 years ago
Read 2 more answers
What things do different atoms have in common?<br><br> Thank you!
prohojiy [21]

Answer:They come in different kinds, called elements, but each atom shares certain characteristics in common. All atoms have a dense central core called the atomic nucleus. Forming the nucleus are two kinds of particles: protons, which have a positive electrical charge, and neutrons, which have no charge

Explanation:

4 0
2 years ago
1) A net force of 75.5 N is applied horizontally to slide a 225 kg crate across the floor.
dimulka [17.4K]

Answer:

The acceleration of the crate is 0.3356\,\frac{m}{s^2}

Explanation:

Recall the formula that relates force,mass and acceleration from newton's second law;

F=m\,a

Then in our case, we know the force applied and we know the mass of the crate, so we can solve for the acceleration as shown below:

F=m\,a\\75.5\,N=225\,\,kg\,\,a\\a=\frac{75.5}{225} \,\frac{m}{s^2} \\a=0.3356\,\,\frac{m}{s^2}

7 0
3 years ago
Pls help in these 2 questions
Nadya [2.5K]

Answer:

Taking forces along the plane

F cos θ - M g sin θ -100 = M a       net of forces along the plane

F = (M a + M g * .5 + 100) / .866     solving for F

F = (80 * 1.5 + 80 * 9.8 * .5 + 100) / .866 = 707 N

F = 707 N acting along the plane

Fn = F sin θ + M g cos θ       forces acting perpendicular to plane

Fn = 707 * 1/2 + 80 * 9.8 * .866 = 1030 Newtons   forces normal to plane

(this would give a coefficient of friction of 100 / 1030 = .097 = Fn)

4 0
2 years ago
A plane passes over Point A with a velocity of 8000 m/s north. Forty seconds later it passes over Point B at a velocity of 10,00
Airida [17]

Answer:

The planes’ acceleration from A to B is 500m/s^2

Explanation:

Given that the initial velocity u is 8000m/s

and also given the final velocity v=10,000 m/s

the time taken to move from A to B = 40 second

The acceleration is defined as the rate of change of velocity with time

we know that the expression for acceleration is given as

a=(v-u)/t

substituting our given data into the expression for a we have

a=(10000-8000)/40

a=2000/40

a=500m/s^2

The planes’ acceleration from A to B is 500m/s^2

7 0
3 years ago
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