Answer:
length f′0 when the eye is presbyopic and by a screen (the retina) at the distance d from the
Explanation:
Answer : Noble Gases do not readily form compounds because they are chemically stable with 8 valence electrons.
Explanation :
Noble gases are the chemical elements that are present in group 18 in the periodic table.
The elements are helium, neon, argon, krypton, xenon and radon.
They are chemically most stable except helium due to having the maximum number of 8 valence electrons can hold their outermost shell that means they have a complete octet.
They are rarely reacts with other elements to form compounds by gaining or losing electrons since they are already chemically stable.
Hence, the noble Gases do not readily form compounds because they are chemically stable with 8 valence electrons.
Answer:
0.247 μC
Explanation:
As both sphere will be at the same level at wquilibrium, the direction of the electric force will be on the x axis. As you can see in the picture below, the x component of the tension of the string of any of the spheres should be equal to the electric force of repulsion. And its y component will be equal to the weight of one sphere. We can use trigonometry to find the components of the tensions:
![F_y: T_y - W = 0\\T_y = m*g = 0.002 kg *9.81m/s^2 = 0.01962 N](https://tex.z-dn.net/?f=F_y%3A%20%20T_y%20-%20W%20%3D%200%5C%5CT_y%20%3D%20m%2Ag%20%3D%200.002%20kg%20%2A9.81m%2Fs%5E2%20%3D%200.01962%20N)
![T_y = T_*cos(50)\\T = \frac{T_y}{cos(50)} = 0.0305 N](https://tex.z-dn.net/?f=T_y%20%3D%20T_%2Acos%2850%29%5C%5CT%20%3D%20%5Cfrac%7BT_y%7D%7Bcos%2850%29%7D%20%3D%200.0305%20N)
![T_x = T*sin(50) = 0.0234 N](https://tex.z-dn.net/?f=T_x%20%3D%20T%2Asin%2850%29%20%3D%200.0234%20N)
The electric force is given by the expression:
![F = k*\frac{q_1*q_2}{r^2}](https://tex.z-dn.net/?f=F%20%3D%20k%2A%5Cfrac%7Bq_1%2Aq_2%7D%7Br%5E2%7D)
In equilibrium, the distance between the spheres will be equal to 2 times the length of the string times sin(50):
![r = 2*L*sin(50) = 2 * 0.1m * sin(50) 0.1532 m](https://tex.z-dn.net/?f=r%20%3D%202%2AL%2Asin%2850%29%20%3D%202%20%2A%200.1m%20%2A%20sin%2850%29%200.1532%20m)
And k is the coulomb constan equal to 9 *10^9 N*m^2/C^2. q1 y q2 is the charge of each particle, in this case, they are equal.
![F_x = T_x - F_e = 0\\T_x = F_e = k*\frac{q^2}{r^2}](https://tex.z-dn.net/?f=F_x%20%3D%20T_x%20-%20F_e%20%3D%200%5C%5CT_x%20%3D%20F_e%20%3D%20k%2A%5Cfrac%7Bq%5E2%7D%7Br%5E2%7D)
![q = \sqrt{T_x *\frac{r^2}{k}} = \sqrt{0.0234 N * \frac{(0.1532m)^2}{9*10^9 N*m^2/C^2} } = 2.4704 * 10^-7 C](https://tex.z-dn.net/?f=q%20%3D%20%5Csqrt%7BT_x%20%2A%5Cfrac%7Br%5E2%7D%7Bk%7D%7D%20%3D%20%5Csqrt%7B0.0234%20N%20%2A%20%5Cfrac%7B%280.1532m%29%5E2%7D%7B9%2A10%5E9%20N%2Am%5E2%2FC%5E2%7D%20%7D%20%3D%202.4704%20%2A%2010%5E-7%20C)
O 0.247 μC
Answer:
![F'=2F](https://tex.z-dn.net/?f=F%27%3D2F)
Explanation:
The Coulomb's law states that the magnitude of the electrostatic force between two charges is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them:
![F=\frac{kq_1q_2}{d^2}](https://tex.z-dn.net/?f=F%3D%5Cfrac%7Bkq_1q_2%7D%7Bd%5E2%7D)
In this case, we have
:
![F'=\frac{kq'_1q_2}{d^2}\\F'=\frac{k(2q_1)q_2}{d^2}\\F'=2\frac{kq_1q_2}{d^2}\\F'=2F](https://tex.z-dn.net/?f=F%27%3D%5Cfrac%7Bkq%27_1q_2%7D%7Bd%5E2%7D%5C%5CF%27%3D%5Cfrac%7Bk%282q_1%29q_2%7D%7Bd%5E2%7D%5C%5CF%27%3D2%5Cfrac%7Bkq_1q_2%7D%7Bd%5E2%7D%5C%5CF%27%3D2F)
The answer is : D
Reasoning:
Homeostasis is the body’s balance