Answer:
Explanation:
In optics, the refractive index of a material is a dimensionless number that describes how fast light travels through the material. It is defined as where c is the speed of light in vacuum and v is the phase velocity of light in the medium or for short the ratio of the velocity of light in a vacuum to its velocity in a specified medium.
Answer: The correct answer is balanced force.
Explanation:
Balanced forces are balanced when the forces are acting equal in magnitude but opposite in direction. The balanced forces will not cause change in the speed of the object.
Unbalanced forces are unbalanced when the forces acting on the object are not equal in magnitude. The combined force is the difference between the forces. It will cause the change in the speed of the body.
Therefore, forces that are equal in size but opposite in direction are balanced.
Answer:
b= 2.14 m
Explanation:
Given that
Weight of the board ,wt = 40 N
Wight of the first children , wt₁=500 N
Weight of the second children ,wt₂ = 350 N
The distance of the 500 N child from center ,a= 1.5 m
lets take distance of the 350 N child from center = b m
Now by taking the moment about the center of the board
We know that moment = Force x Perpendicular distance from the force
wt₁ x a = wt₂ x b
500 x 1.5 = 350 x b
b= 2.14 m
Therefore the distance of the 350 N weight child from the center is 2.14 m.
Answer: a) 7,00 centimeters
(b) 259. 19 feet
(c) 3110.28 inches
(d) 0.049 miles
Explanation:
(a) We know that 1 meter = 100 centimeters
Therefore,

(b)Since 1 meter = 3.28084 feet
Then, 
(c) Since, 1 feet = 12 inches.

(d) 

The moon's orbital plane is different from that of the earth's orbit around the sun due to which lunar and solar eclipses do not occur every month.
<h3 /><h3>What is a solar eclipse?</h3>
When the moon passes in front of Earth and the sun, it creates a solar eclipse and casts a shadow across the globe.
Only during the new moon phase, when the moon travels squarely between the sun and Earth and casts shadows on its surface, can a solar eclipse occur.
Due to the moon's orbit being five degrees off-center from Earth's orbit around the Sun, lunar eclipses do not happen every month and the Moon often passes above or below the shadow.
Lunar eclipses would happen every month if there were no tilt. Eclipses of the sun and the moon happen equally often.
Hence lunar and solar eclipses aren't coming every month.
To learn more about the solar eclipse refer;
brainly.com/question/17749647
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