Answer:
D. They have the same number of valence electrons
Explanation:
In order to answer this question we need to understand the following.
- Valence electrons refers to the outermost electron(s) in the outermost energy level of an atom.
- Elements in the same group in the periodic table have the same number of valence electrons. For instance, group 2A elements have 2 valence electrons.
- The reactivity of elements in the periodic table is based on the number of valence electrons and the ease of gaining or losing electrons.
- Elements in the same group have similar valence electrons and therefore share similar chemical properties such as reactivity.
- Hence, elements in the same group have same number of valence electron and will thus have similar reactivity.
Answer:
2s
Explanation:
The position function of the motion can be expressed as:

where
is the origin where the particle starts off,
and a = <1,2,0> m/s2. In the 3-coordinate system it can be written as

For the particle to hit the 2x+y-z=4 plane then its coordinates must meet that criteria



t = 2 or t = -1
Since t can only be positive we will pick t = 2s
Answer:
the maximum current is 500 A
Explanation:
Given the data in the question;
the B field magnitude on the surface of the wire is;
B = μ₀i / 2πr
we are to determine the maximum current so we rearrange to find i
B2πr = μ₀i
i = B2πr / μ₀
given that;
diameter d = 2 mm = 0.002 m
radius = 0.002 / 2 = 0.001 m
B = 0.100 T
we know that permeability; μ₀ = 4π × 10⁻⁷ Tm/A
so we substitute
i = (0.100)(2π×0.001 ) / 4π × 10⁻⁷
i = 500 A
Therefore, the maximum current is 500 A
Well, it's up on top of a pole or pedestal of some sort,
so it has some gravitational potential energy relative to
the ground. In other words, if it somehow became detached
from its structure and fell to the ground, it would make quite
an energetic splat when it got there.
Also, the windmill is at the temperature of the air around it,
which is far from Absolute Zero, so the windmill holds a lot of
thermal (heat) energy.
Then I guess there's the matter of the chemical energy in the
molecules of the material that the windmill is made of, and the
nuclear energy in its atoms.