A) The resultant force is 30.4 N at ![25.3^{\circ}](https://tex.z-dn.net/?f=25.3%5E%7B%5Ccirc%7D)
B) The resultant force is 18.7 N at ![43.9^{\circ}](https://tex.z-dn.net/?f=43.9%5E%7B%5Ccirc%7D)
Explanation:
A)
In order to find the resultant of the two forces, we must resolve each force along the x- and y- direction, and then add the components along each direction to find the components of the resultant.
The two forces are:
at
above x-axis
at
above y-axis
Resolving each force:
![F_{1x}=F_1 cos \theta = (20)(cos 0)=20 N\\F_{1y}=F_1 sin \theta =(20)(sin 0)=0 N](https://tex.z-dn.net/?f=F_%7B1x%7D%3DF_1%20cos%20%5Ctheta%20%3D%20%2820%29%28cos%200%29%3D20%20N%5C%5CF_%7B1y%7D%3DF_1%20sin%20%5Ctheta%20%3D%2820%29%28sin%200%29%3D0%20N)
![F_{2x}=F_2 cos \theta = (15)(cos 60)=7.5 N\\F_{2y}=F_2 sin \theta =(15)(sin 60)=13.0 N](https://tex.z-dn.net/?f=F_%7B2x%7D%3DF_2%20cos%20%5Ctheta%20%3D%20%2815%29%28cos%2060%29%3D7.5%20N%5C%5CF_%7B2y%7D%3DF_2%20sin%20%5Ctheta%20%3D%2815%29%28sin%2060%29%3D13.0%20N)
So, the components of the resultant are:
![F_x = F_{1x}+F_{2x}=20+7.5 = 27.5 N\\F_y = F_{1y}+F_{2y}=0+13.0=13.0 N](https://tex.z-dn.net/?f=F_x%20%3D%20F_%7B1x%7D%2BF_%7B2x%7D%3D20%2B7.5%20%3D%2027.5%20N%5C%5CF_y%20%3D%20F_%7B1y%7D%2BF_%7B2y%7D%3D0%2B13.0%3D13.0%20N)
And the magnitude of the resultant is:
![F=\sqrt{F_x^2+F_y^2}=\sqrt{27.5^2+13.0^2}=30.4 N](https://tex.z-dn.net/?f=F%3D%5Csqrt%7BF_x%5E2%2BF_y%5E2%7D%3D%5Csqrt%7B27.5%5E2%2B13.0%5E2%7D%3D30.4%20N)
And the direction is:
![\theta=tan^{-1}(\frac{F_y}{F_x})=tan^{-1}(\frac{13.0}{27.5})=25.3^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%3Dtan%5E%7B-1%7D%28%5Cfrac%7BF_y%7D%7BF_x%7D%29%3Dtan%5E%7B-1%7D%28%5Cfrac%7B13.0%7D%7B27.5%7D%29%3D25.3%5E%7B%5Ccirc%7D)
B)
In this case, the 15 N is applied in the opposite direction to the 20 N force. Therefore we need to re-calculate its components, keeping in mind that the angle of the 15 N force this time is
![\theta=180^{\circ}-60^{\circ}=120^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%3D180%5E%7B%5Ccirc%7D-60%5E%7B%5Ccirc%7D%3D120%5E%7B%5Ccirc%7D)
So we have:
![F_{2x}=F_2 cos \theta = (15)(cos 120)=-7.5 N\\F_{2y}=F_2 sin \theta =(15)(sin 120)=13.0 N](https://tex.z-dn.net/?f=F_%7B2x%7D%3DF_2%20cos%20%5Ctheta%20%3D%20%2815%29%28cos%20120%29%3D-7.5%20N%5C%5CF_%7B2y%7D%3DF_2%20sin%20%5Ctheta%20%3D%2815%29%28sin%20120%29%3D13.0%20N)
So, the components of the resultant this time are:
![F_x = F_{1x}+F_{2x}=20-7.5 = 12.5 N\\F_y = F_{1y}+F_{2y}=0+13.0=13.0 N](https://tex.z-dn.net/?f=F_x%20%3D%20F_%7B1x%7D%2BF_%7B2x%7D%3D20-7.5%20%3D%2012.5%20N%5C%5CF_y%20%3D%20F_%7B1y%7D%2BF_%7B2y%7D%3D0%2B13.0%3D13.0%20N)
And the magnitude is:
![F=\sqrt{F_x^2+F_y^2}=\sqrt{13.5^2+13.0^2}=18.7 N](https://tex.z-dn.net/?f=F%3D%5Csqrt%7BF_x%5E2%2BF_y%5E2%7D%3D%5Csqrt%7B13.5%5E2%2B13.0%5E2%7D%3D18.7%20N)
And the direction is:
![\theta=tan^{-1}(\frac{F_y}{F_x})=tan^{-1}(\frac{13.0}{13.5})=43.9^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%3Dtan%5E%7B-1%7D%28%5Cfrac%7BF_y%7D%7BF_x%7D%29%3Dtan%5E%7B-1%7D%28%5Cfrac%7B13.0%7D%7B13.5%7D%29%3D43.9%5E%7B%5Ccirc%7D)
Learn more about vector addition:
brainly.com/question/4945130
brainly.com/question/5892298
#LearnwithBrainly
<span>reflection, rotation, translation</span>
Electron configurations:
Ge: [Ar] 3d10 4s2 4p2 => 6 electrons in the outer shell
Br: [Ar] 3d10 4s2 4p5 => 7 electrons in the outer shell
Kr: [Ar] 3d10 4s2 4p6 => 8 electrons in the outer shell
The electron affinity or propension to attract electrons is given by the electronic configuration. Remember that the most stable configuration is that were the last shell is full, i.e. it has 8 electrons.
The closer an atom is to reach the 8 electrons in the outer shell the bigger the electron affinity.
Of the three elements, Br needs only 1 electron to have 8 electrons in the outer shell, so it has the biggest electron affinity (the least negative).
Ge: needs 2 electrons to have 8 electrons in the outer shell, so it has a smaller (more negative) electron affinity than Br.
Kr, which is a noble gas, has 8 electrons and is not willing to attract more electrons at all, the it has the lowest (more negative) electron affinity of all three to the extension that really the ion is so unstable that it does not make sense to talk about a number for the electron affinity of this atom.
Answer:
<em>The kinetic energy of a spinning disk will be reduced to a tenth of its initial kinetic energy if its moment of inertia is made five times larger, but its angular speed is made five times smaller.</em>
<em></em>
Explanation:
Let us first consider the initial characteristics of the angular motion of the disk
moment of inertia = ![I](https://tex.z-dn.net/?f=I)
angular speed = ω
For the second case, we consider the characteristics to now be
moment of inertia =
(five times larger)
angular speed = ω/5 (five times smaller)
Recall that the kinetic energy of a spinning body is given as
![KE = \frac{1}{2}Iw^{2}](https://tex.z-dn.net/?f=KE%20%3D%20%5Cfrac%7B1%7D%7B2%7DIw%5E%7B2%7D)
therefore,
for the first case, the K.E. is given as
![KE = \frac{1}{2}Iw^{2}](https://tex.z-dn.net/?f=KE%20%3D%20%5Cfrac%7B1%7D%7B2%7DIw%5E%7B2%7D)
and for the second case, the K.E. is given as
![KE = \frac{1}{2}(5I)(\frac{w}{5} )^{2} = \frac{5}{50}Iw^{2}](https://tex.z-dn.net/?f=KE%20%3D%20%5Cfrac%7B1%7D%7B2%7D%285I%29%28%5Cfrac%7Bw%7D%7B5%7D%20%29%5E%7B2%7D%20%20%20%3D%20%5Cfrac%7B5%7D%7B50%7DIw%5E%7B2%7D)
![KE = \frac{1}{10}Iw^{2}](https://tex.z-dn.net/?f=KE%20%3D%20%5Cfrac%7B1%7D%7B10%7DIw%5E%7B2%7D)
<em>this is one-tenth the kinetic energy before its spinning characteristics were changed.</em>
<em>This implies that the kinetic energy of the spinning disk will be reduced to a tenth of its initial kinetic energy if its moment of inertia is made five times larger, but its angular speed is made five times smaller.</em>