-1- was created in the 1600 by william gilbert
-2-When the charge is positive, electrons in the metal of the electroscope are attracted to the charge and move upward out of the leaves. This results in the leaves to have a temporary positive charge and because like charges repel, the leaves separate. When the charge is removed, the electrons return to their original positions and the leaves relax
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An electroscope is made up of a metal detector knob on top which is connected to a pair of metal leaves hanging from the bottom of the connecting rod. When no charge is present the metals leaves hang loosely downward. But, when an object with a charge is brought near an electroscope, one of the two things can happen.
<h2>Answer: electrostatic and gravitational force
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Mechanical energy remains constant (conserved) if only <u>conservative forces</u> act on the particles.
In this sense, the following forces are conservative:
-Gravitational
-Elastic
-Electrostatics
While the Friction Force and the Magnetic Force are not conservative.
According to this, mechanical energy is conserved in the presence of electrostatic and gravitational forces.
1) A negatively charged ion is chloride
2) Moving from left to right, valence electrons increase by one.
3) The period number gives information about how many energy levels it has
4) Fluorine has a charge of 1–
5) Potassium and iodine form an ionic bond
The periodic table is an arrangement of elements into groups and periods based on their periodic properties.
In the periodic table, elements are arranged in groups and periods. There are 18 groups and 8 periods.
Chlorine is in group 17, there have seven outermost electrons hence the chlorine atom needs only one more electron in order to attain a stable octet. This is done by accepting one electron to form the negatively charged chloride ion.
As we move from one period to another, one extra electron is added to the outermost shell of elements. Hence, the valence electrons increases by one.
The period to which an element belongs shows you the number of shells or energy levels in the atom of that element.
Fluorine is in group 17. One electron is needed to achieve a stable octet. When an atom accepts one electron, its charge is 1–.
Bonding based on ionic charges occurs between metals and nonmetals. Potassium is a metal of group 1 and iodine is a non metal of group 17 hence they can bond together based on their ionic charges.
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Gravity is a non contact force , jump from a little high place (don't do that :P) , you wont just get stuck in the air you will fall down , this is gravity you dont need any contact
The answers is A and C hope this helps :)