Answer:
4 A
Explanation:
The relationship between current, voltage and resistance in a circuit is given by Ohm's law:

where
V is the voltage
R is the resistance
I is the current
The equation can also be rewritten as

from which we see that the current is inversely proportional to the resistance, R.
In this problem, the initial current is I = 8 A. Then the resistance is doubled:
R ' = 2R
So the new current is

so the current is halved.
Answer:
A : hot and moist, maritime tropical
B: cold and dry, maritime polar
C: hot and moist , maritime tropical
D: cold and dry, continental polar
E: hot and moist , maritime tropical
F: cold and dry , maritime polar
Explanation:
Cold air is denser than warm air. The more water vapor that is in the air, the less dense the air becomes. That is why cold, dry air is much heavier than warm, humid air.
Maritime polar (mP) air masses are cool, moist, and unstable. Some maritime polar air masses originate as continental polar air masses over Asia and move westward over the Pacific, collecting warmth and moisture from the ocean.
Maritime tropical (mT) air masses are warm, moist, and usually unstable.
Answer:
Option b. Effective nuclear charge increases as we move to the right across a row in the periodic table
Explanation:
The <em>effective nuclear charge </em>is a measure of how strong the protons in the nucleus of an atom attract the outermost electrons of such atom.
The <em>effective nuclear charge</em> is the net positive charge experienced by valence electrons and is calculated (as an approximation) by the equation: Zeff = Z – S, where Z is the atomic number and S is the number of shielding electrons.
The shielding electrons are those electrons in between the interesting electrons and the nucleus of the atom.
Since the shielding electrons are closer to the nucleus, they repel the outermost electrons and so cancel some of the attraction exerted by the positive charge of the nucleus, meaning that the outermost electrons feel less the efect of attraction of the protons. That is why in the equation of Zeff, the shielding electrons (S) subtract the total from the atomic number Z.
The <em>effective nuclear charge</em>, then, is responsible for some properties and trends in the periodic table. Here, you can see how this explains the trend of the atomic radius (size of the atom) accross a row in the periodic table.
- As the<em> effective nuclear charge</em> is larger, in a same row of the periodic table, the shielding effect is lower, the outermost electrons are more strongly attracted by the nucleus, and the size of the atoms decrease. That is why as we move to the right in the periodic table, the size of the atoms decrease.
Answer:

Explanation:
The frequency of a wave can be found using the following formula.

where <em>f</em> is the frequency, <em>v</em> is the velocity/wave speed, and λ is the wavelength.
The wavelength is 10 meters and the velocity is 200 meters per second.
- 1 m/s can also be written as 1 m*s^-1
Therefore:

Substitute the values into the formula.

Divide and note that the meters (m) will cancel each other out.


- 1 s^-1 is equal to Hertz
- Therefore, our answer of 20 s^-1 is equal to 20 Hz

The frequency of the wave is <u>20 Hertz</u>
Answer:
The correct solution is "14.6875 kg".
Explanation:
Given values:
Force,
F = 47.0 N
Acceleration,
a = 3.20 m/s²
Now,
⇒ 
or,
⇒ 
⇒ 
⇒ 
⇒ 