<h2>
Answer: Infrared light</h2>
A dark nebula is a cloud of dust and cold gas, which does not emit visible light and hides the stars it contains.
These types of nebulae are composed mainly of the hydrogen they obtain from nearby stars, which is their fuel.
It is using infrared light that we can "observe" and analyze in detail what happens in the inner parts of these nebulae.
Answer:
Part a)

Part b)

Explanation:
As per momentum conservation we know that there is no external force on this system so initial and final momentum must be same
So we will have




Part b)
By equation of kinetic energy we have




Answer: it would be A
Explanation: how are we to measure the air of a square mile
Yes. A glacier is nothing more than a huge mineral flowing downhill.
Answer:
7.23407 
Explanation:
(I will not include units in calculations)
I'm assuming FBD's are already drawn, so I will work from there.
Let the 2.2kg block equal
, and the 20kg block equal
.
Summation equation for
:
, 
Summation equation for
: 
Torque Summation Equation: 
Do some plugging in with the values given: 
Replace
with
, and cancel out the r's.
This step is important: Rearrange the force summation equation to solve for each tension force.

Perform Substitution: 
Now, we need to find the friction force and the horizontal component of the force of gravity.
Note that
μ
And based on our earlier summation equation: 
First, break
into x and y components.
, 
Perform substitution with this and the fact that
.

Solving for a, plugging in numbers yields an answer of 7.23407 