The difference between the above velocities is that they exist in opposite direction of each other. or it can be said that they are negative vectors of each other.
Answer:


Explanation:

Required
The units of A and B
From the question, we understand that:

This implies that each of
and
will have the same unit as 
So, we have:


The unit of t is (s); So, the expression becomes

Divide both sides by 


Answer:
D) Some of the light passes through, and some of the light is absorbed or scattered by the object.
Explanation:
When light strikes translucent materials, only some of the light passes through them. The light does not pass directly through the materials. ... When light strikes an opaque object none of it passes through. Most of the light is either reflected by the object or absorbed and converted to heat.
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The best position for the person would be outside, under a clear sky, standing up. He should do it sometime between sunset and sunrise, from a day before until a day after the moment of Full Moon.
Answer:
1.
2.
3.The results from part 1 and 2 agree when r = R.
Explanation:
The volume charge density is given as

We will investigate this question in two parts. First r < R, then r > R. We will show that at r = R, the solutions to both parts are equal to each other.
1. Since the cylinder is very long, Gauss’ Law can be applied.

The enclosed charge can be found by integrating the volume charge density over the inner cylinder enclosed by the imaginary Gaussian surface with radius ‘r’. The integration of E-field in the left-hand side of the Gauss’ Law is not needed, since E is constant at the chosen imaginary Gaussian surface, and the area integral is

where ‘h’ is the length of the imaginary Gaussian surface.

2. For r> R, the total charge of the enclosed cylinder is equal to the total charge of the cylinder. So,

3. At the boundary where r = R:

As can be seen from above, two E-field values are equal as predicted.