Answer:
Explanation:
Length if the bar is 1m=100cm
The tip of the bar serves as fulcrum
A force of 20N (upward) is applied at the tip of the other end. Then, the force is 100cm from the fulcrum
The crate lid is 2cm from the fulcrum, let the force (downward) acting on the crate be F.
Using moment
Sum of the moments of all forces about any point in the plane must be zero.
Let take moment about the fulcrum
100×20-F×2=0
2000-2F=0
2F=2000
Then, F=1000N
The force acting in the crate lid is 1000N
Option D is correct
1. H2O- The water completely dissolved the salt.
Alcohol- The alcohol dissolved the salt slightly.
Glycerin-The salt has not dissolved at all.
2. Water
3. Like dissolve like basically works on the principle of polarity. It means the substances which possess similar chemical properties may dissolve in each other. For example, ethanol can be dissolved in water because both are polar in nature whereas non-polar molecules can be dissolved in non-polar solvents only.
4. Generally, a solute dissolves faster in a warmer solvent than it does in a cooler solvent because particles have more energy of movement. For example, if you add the same amount of sugar to a cup of hot tea and a cup of iced tea, the sugar will dissolve faster in the hot tea.
Learn more about The choice of solvent here:-brainly.com/question/14918321
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Answer:
For an atom to have a balanced charged, the number of protons shall be equal to the number of electrons of an atom. proton is the positive part of an atom whereas electrons are the negative part of an atom. Only if the number of protons will be equal to the number of electron, the atom will be able to be neutral.
If the number of electron will be more, then the atom will be negative. If the number of electron will be less, then the atom will be positive.
The main requirement for a good conductor of electricity is to have a lot of valence electrons. Valence electrons are the electrons of the outer shells of atoms not bound with other atoms (for example through covalent bounds). These electrons are "free to escape" as soon as an electric field with enough intensity is applied to the material, and therefore these electrons will be free to move in the material producing an electric current.