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Dvinal [7]
2 years ago
11

Geological evidence based on several radiometric techniques has provided a scientifically well-accepted age for the Earth. Repre

sent that age of the Earth as the 100-yard length of a football field, and any time interval can be represented as some distance on the field. (So something that lasted one-tenth of the age of the Earth would be ten yards, and something that lasted one-half of the age of the Earth would be fifty yards.) On this scale, the time from when dinosaur extinction made space for large mammals, until today, would be represented by how far on the football field?
a. A little over 1 yard.
b. Over 90 yards.
c. 60 yards.
d. Over 80 yards.
e. 50 yards.
Physics
1 answer:
lidiya [134]2 years ago
3 0
Considering earth is 4.5 billion years old and dinosaurs only went extinct 66 million ago o would say Answer: A - a little over one yard
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nika2105 [10]

Answer:

0.000003782 m

0.000001891 m

0.000001197125 m

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D = Diameter of beam = 1 cm

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The angle is given by

\theta=\dfrac{1.22\lambda}{D}

The width is given by

d=2\theta f\\\Rightarrow d=2\dfrac{1.22\lambda f}{D}\\\Rightarrow d=2\dfrac{1.22\times 248\times 10^{-9}\times 6.25\times 10^{-2}}{1\times 10^{-2}}\\\Rightarrow d=0.000003782\ m

The required width is 0.000003782 m

Minimum resolvable line separation is given by

\dfrac{0.000003782}{2}=0.000001891\ m

The minimum resolvable line separation between adjacent lines is 0.000001891 m

when \lambda=157\ nm

d=2\dfrac{1.22\times 157\times 10^{-9}\times 6.25\times 10^{-2}}{1\times 10^{-2}}\\\Rightarrow d=0.00000239425\ m

The new minimum resolvable line separation between adjacent lines is

\dfrac{0.00000239425}{2}=0.000001197125\ m

6 0
2 years ago
Waves hitting at an angle and then bending around features of the coast is known as
Pavel [41]
<span>Waves hitting at an angle and then bending around features of the coast is known as Wave refraction
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6 0
2 years ago
A gas of helium atoms at 273 k is in a cubical container with 25.0 cm on a side. (a) what is the minimum uncertainty in momentum
qwelly [4]

wave function of a particle with mass m is given by ψ(x)={ Acosαx −

π

2α

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π

2α

0 otherwise , where α=1.00×1010/m.

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(b) Find the probability that the particle can be found on the interval 0≤x≤0.5×10−10m.

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6 0
2 years ago
You decide to work at a heart rate of 150 instead of 120. What area of F.I.T.T. did you change?
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Key concepts

Heart rate

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i think it will help you...if it help you ...please mark brainless

8 0
2 years ago
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The volume of the room is the product of its dimensions:

10\times 12 \times 4 = 480\text{ m}^3

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m=dV

So, multiply the density and the volume to get the mass of air in the room.

7 0
2 years ago
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