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dsp73
3 years ago
9

How many elements did mendeleev place in group 2​

Physics
1 answer:
Pepsi [2]3 years ago
8 0

Answer:5

Explanation:

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Light with a wavelength of about 490 nm is made to pass through a diffraction grating. the angle formed between the path of the
polet [3.4K]

The number of lines per mm in the diffraction grating is 326.

<h3>What is diffraction grating?</h3>

A diffraction grating is a type of optical instrument obtained with a continuous pattern. The pattern of the diffracted light by a grating depends on the structure and number of elements present.

The given data in the problem is

\rm \theta is the angle formed between the path of the incident light and the diffracted light = 9. 2°

λ is the wavelength of the light=490nm=4.9

N is the number of lines per mm in the diffraction grating=?

n is ordered = 1

The formula for the diffraction grating is;

n \lambda = d sin\theta \\\\ d = \frac{n \lambda}{sin \theta } \\\\  d = \frac{1 \times 4.90 \times 10^{-7}}{sin 9.2^0 } \\\\ d=3.06 \times 10^{-6} \\\\ d=3.06 \times 10^{-3} \ mm

The number of lines per mm is found as;

\rm N= \frac{1}{d} \\\\ N= \frac{1}{3.06 \TIMES 10^{-3}} \\\\ N=326.8 /mm

Hence the number of lines per mm in the diffraction grating is 326.

To learn more about diffraction grating refer to the link;

brainly.com/question/1812927

5 0
2 years ago
Give two examples from the fossil record that show evidence of change in the complexity of organisms over time.
polet [3.4K]

Answer:

Fossils tell us when organisms lived, as well as provide evidence for the progression and evolution of life on earth over millions of years.

Explanation:

As the world changes, plants and animals change with it. Aside from a few living fossils, the species we see today are very different from species that lived in the past. Thus, the fossil record can be used to show that organisms changed to meet new conditions. ... This is the result of evolution of species over time.

8 0
2 years ago
What is the formula for work?
babunello [35]
W = F • d • cos(theta)

6 0
3 years ago
A giant armadilo moving northward with a constant acceleration covers the distance between two points 60m apart in 6 seconds. It
Naddika [18.5K]
Acceleration is the rate of change of the velocity of an object that is moving. This value is a result of all the forces that is acting on an object which is described by Newton's second law of motion. To determine acceleration, we need to know the initial velocity and the final velocity and the time elapsed. From the given values, we need t o calculate for the initial velocity. We use some kinematic equations. We do as follows:

 x = v0t + at^2/2
60 = v0(6) + a(6)^2/2
60 = 6v0 + 18a          (EQUATION 1)

vf = v0 + at
15 = v0 + a(6)
15 = v0 + 6a             (EQUATION 2)

Solving for v0 and a,
v0 = 5 m/s
a = 1.7 m/s^2
8 0
3 years ago
If a weight hanging on a string of length 5 feet swings through 5^\circ on either side of the vertical, how long is the arc thro
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<span>First we can find the circumference of the whole circle with a radius of 5 feet. circumference = 2 pi radius circumference = (2 pi) (5 feet) circumference = (10 pi) feet From one high point to the other high point, the string moves through an angle of 10 degrees. Since a full circle is 360 degrees, this angle is 1/36 of a full circle. Therefore, the arc length is 1/36 of the whole circumference. arc length = (1/36) (circumference) arc length = (1/36) (10 pi) feet arc length = 0.873 feet</span>
7 0
3 years ago
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