Answer:
Parts 1 and 2 only is the best answer.
Explanation:
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Depending on what you are working with, it would be a solid
We have: K.E. = mv² / 2
Here, m = 1 Kg
v = 4 m/s
Substitute their values in the formula,
K.E. = 1×4² / 2
K.E. = 16/ 2
K.E. = 8 J
Finally, answer of your question would be 8 Joules.
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Answer:
The grating spacing of the beetle is 
Explanation:
The concept to solve this problem is relate to interference effect given in the Young's Slits. Here was demonstrated that the length of the side labelled \lambda is known as the path difference. The equation is given by,

Where,
= wavelenght of light
N = a positive integer: 1,2,3...
= Angle from the center of the wall to the dark spot
d= width of the slit
Replacing our values we have that for n=1,



Therefore the grating spacing of the beetle is 
<span>Generators use the magnetic field of "Permanent Magnets"
In short, Your Answer would be Option D
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