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Answer:</h2>
Dark matter is a type of matter, whose composition is unknown and which corresponds to 80% of the matter in the universe. Its name refers to the fact it does not emit or interact with any type of electromagnetic radiation, being completely transparent throughout the electromagnetic spectrum.
However, it interacts with the known matter through <u>gravity</u>.
In this sense, it is believed that the Milky Way has 90% dark matter and only 10% ordinary matter (known matter). Because, like gravity, dark matter can not be observed directly, however its existence is inferred through the movement of the stars and the cosmic dust within the galaxy.
Answer:
lamda=10.5m
Explanation:
using the equation of progressive wave.
y=Asin(wt-kx)
comparing the two equations together, we have
kx=0.6x , k=0.6
k=2π/λ
0.6=2*3.142/λ
cross multiply
0.6λ=6.284
divide both sides by 0.6
λ=6.284/0.6
λ=10.47m
approximate
λ=10.5m
Using the two kinematic equations that can be used for this problem are:
Vf = Vi + at and d=Vit +(1/2)*at^2
Since Vi (initial velocity) = 0
The equations can further be simplified where a is the acceleration, t is the time, Vf is the final velocity which is 70 miles per hour and d is 6 miles
Vf = at
70 = at
a = 70/t---equation 1
d=(1/2)*a*(t^2)
6 = (1/2)*a*(t^2) ---equation 2
Substituting equation 1 to equation 2.
6= (1/2)*(70/t)*(t^2)
6= 35t
t= 0.17142 hours or 10.28571 mins or 617.14 sec
