Answer:
The intensity I₂ of the light beam emerging from the second polarizer is zero.
Explanation:
Given:
Intensity of first polarizer = Io/2
For the second polarizer, the intensity is equal:
Answer:
b. the particle must be moving parallel to the magnetic field.
Explanation:
The magnetic force on a moving charged particle is given by;
F = qvBsinθ
where;
q is the charge of the particle
v is the velocity of the particle
B is the magnetic field
θ is the angle between the magnetic field and velocity of the moving particle.
When is the charge is stationary the magnetic force on the charge is zero.
Also when the charge is moving parallel to the magnetic field, the magnetic force is zero.
Therefore, when a moving charged particle experiences no magnetic force, we can definitely conclude that the particle must be moving parallel to the magnetic field.
b. the particle must be moving parallel to the magnetic field.
Elements in group 2 are called alkaline earth metals, the most similarity about the alkaline metals is which chemical properties they have.
<h2>Further Explanation
</h2><h3>Periodic table </h3>
- Periodic table is a table that contains elements arranged in columns called groups and rows called periods.
- Elements are arranged based on physical and chemical properties such that elements in the same group will have similar physical and chemical properties.
<h3>Chemical families </h3>
- Based on the chemical properties elements belong to a family of elements sharing similar chemical or physical characteristics.
- Examples of common chemical families include; alkali metals, alkaline-earth metals, halogens and noble gases among others.
<h3>Alkaline-earth metals </h3>
- These are elements that are found in group 2 of the periodic table. Alkaline-earth metals include, Beryllium, Magnesium, Calcium, Strontium, Barium, and Radium.
Properties of Alkaline-earth metals
- Alkaline earth metals have a valence of two since they form ions by losing two electrons from their outermost energy levels.
- Unlike the Alkali metals, the earth metals have a smaller atom size and are not as reactive compared to alkali metals.
- Alkaline-earth metals are highly metallic and are good conductors of electricity.
- They react with water and steam to form metal hydroxide and metal oxides respectively
- They react with air to form metal oxides
- Reactivity of alkaline metals depends on the ease of losing electrons, thus the reactivity increases down the group as the number of energy levels increases.
- Additionally, alkaline-earth metals have low electronegativities and low electron affinities
Keywords: Chemical families, alkaline-earth metals, reactivity
<h3>Learn more about: </h3>
Level: High school
Subject: Chemistry
Topic: Periodic table and chemical families
Sub-topic: Alkaline-earth metals
Answer:
Fp = 26.59[N]
Explanation:
This problem can be solved using the principle of work and energy conservation, i.e. the final kinetic energy of a body will be equal to the sum of the forces that do work on the body plus the initial kinetic energy.
We need to identify the initial data:
d = distance = 41.9[m]
Ff = friction force = 44.5 [N]
m = mass = 16.3 [kg]
v1 = 1.9 [m/s]
v2 = 12.6 [m/s]
The kinetic energy at the beginning can be calculated as follows:
![E_{k1}= \frac{1}{2}*m*v_{1}^2 \\E_{k1}= \frac{1}{2}*16.3*(1.9)_{1}^2\\E_{k1}= 29.42[J]](https://tex.z-dn.net/?f=E_%7Bk1%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2Am%2Av_%7B1%7D%5E2%20%5C%5CE_%7Bk1%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2A16.3%2A%281.9%29_%7B1%7D%5E2%5C%5CE_%7Bk1%7D%3D%2029.42%5BJ%5D)
And the final kinetic energy.
![E_{k2}= \frac{1}{2}*m*v_{2}^2 \\E_{k2}= \frac{1}{2}*16.3*(12.6)^2\\E_{k2}= 1294[J]](https://tex.z-dn.net/?f=E_%7Bk2%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2Am%2Av_%7B2%7D%5E2%20%5C%5CE_%7Bk2%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2A16.3%2A%2812.6%29%5E2%5C%5CE_%7Bk2%7D%3D%201294%5BJ%5D)
The work is performed by two forces, the friction force and the pushing force, it is important to clarify that these forces are opposite in direction.
The weight of the cart also performs a work in the direction of movement since the plane is tilted down, this component of the weight of the cart must be parallel to the surface of the inclined plane.
![W_{1-2}=-(44.5*41.9)+(16.3*9.81*sin(17.5)*41.9)+(F_{p}*41.9) \\therefore:\\E_{k1}+W_{1-2}=E_{k2}\\29.42+150.16+(F_{p}*41.9)=1294\\F_{p}=1114.42/41.9\\F_{p}=26.59[N]](https://tex.z-dn.net/?f=W_%7B1-2%7D%3D-%2844.5%2A41.9%29%2B%2816.3%2A9.81%2Asin%2817.5%29%2A41.9%29%2B%28F_%7Bp%7D%2A41.9%29%20%5C%5Ctherefore%3A%5C%5CE_%7Bk1%7D%2BW_%7B1-2%7D%3DE_%7Bk2%7D%5C%5C29.42%2B150.16%2B%28F_%7Bp%7D%2A41.9%29%3D1294%5C%5CF_%7Bp%7D%3D1114.42%2F41.9%5C%5CF_%7Bp%7D%3D26.59%5BN%5D)
