Let car A's starting position be the origin, so that its position at time <em>t</em> is
A: <em>x</em> = (40 m/s) <em>t</em>
and car B has position at time <em>t</em> of
B: <em>x</em> = 100 m - (60 m/s) <em>t</em>
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They meet when their positions are equal:
(40 m/s) <em>t</em> = 100 m - (60 m/s) <em>t</em>
(100 m/s) <em>t</em> = 100 m
<em>t</em> = (100 m) / (100 m/s) = 1 s
so the cars meet 1 second after they start moving.
They are 100 m apart when the difference in their positions is equal to 100 m:
(40 m/s) <em>t</em> - (100 m - (60 m/s) <em>t</em>) = 100 m
(subtract car B's position from car A's position because we take car A's direction to be positive)
(100 m/s) <em>t</em> = 200 m
<em>t</em> = (200 m) / (100 m/s) = 2 s
so the cars are 100 m apart after 2 seconds.
Answer:
14,300 lines per cm
Explanation:
Given that
The wavelength of visible light ranges from 400 nm to 400nm
It is possible to find the maximum number of lines per cm. This maximum number of lines per cm is reciprocal of the least distance separating two adjacent slits, using the following equation.
mλ = dsin (θ), where
m = order of diffraction.
λ = wavelength of the incident light.
d = distance between the centers of the two slits.
θ = angle of diffraction of the mth order.
In order to find the least separation that allows the observation of one complete order of spectrum of the visible region, we make use the maximum or highest wavelength of the visible region that we are given, which is 700 nm.
d = mλ / sin (θ)
Again, we need the distance d to be the smallest, so sin (θ) must be the greatest, and for sin (θ) to be the greatest, it has to be equal to 1. Using the longest wavelength is the best idea because when the smallest wavelength is used the longest wavelength would not be diffracted.
d = mλ / sin (θ)
d = 1 * 700nm / 1
d = 700 nm
Next, we say that
n = 1/d
n = 1 / 700 x
n = 1, 430,000 lines per m, converting to cm, we have n = 14,300 lines per cm
If a motorcycle accelerates from 10 m/s
to 15 m/s in 5 seconds, the average acceleration of the bike is 3 m/s/s. This only
means that the motorcycle’<span>s velocity will increase 3 m/s every second. You need to divide 15 m/s which is the
difference of 10 and 25 to 5 seconds.</span>
All of the rivers in the United States are not monitored closely for pollution levels.
The statement in the question is False
<h3><u>
Explanation:</u></h3>
Not all rivers in the United States are closely monitored for their pollution levels. There are volunteers who take responsibility of checking water bodies such as lakes, rivers, streams etc. They take the next step required after finding a water body contaminated.
But to say that all the rivers receive the same amount of attention and action is incorrect. To ensure that all the rivers are clean and pollution free, it would require a lot of man power in the said department which would collect the water samples from all these rivers and send it to labs for checking the pollution level of the particular river. It can be said that the rivers which are situated beside an industrial site, close to a town, will be the priority for checking pollution levels as it would directly cause harm to a small set of population if the toxicity is at an increased level.
Answer:
It is one of the 7 diatomics
Explanation:
Br
I
N
Cl
H
O
F
^ these are the 7 diatomic molecules. Atoms of these elements exist as a molecule consisting of two covalently bonded atoms of the same element.
Simply put, for these elements, the diatomic state of the atom is much more stable than the unbound one.
