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Divisibility

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Divisibility Divisibility Check the Divisibility by 2,4,8,5 Check the Divisibility by 3,6,9> Check the Divisibility by 7 Check the Divisibility by 11 Check the Divisibility by 13 Check the Divisibility by 17

class 9 chemistry practice Questions

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Science  Date :- 27/01/2023 :  Atomic Structure   Short & very short answer type Questions.   Write the names of three elementary particles which constitute an atom.  Which is heavier, neutron or proton? How many times a proton is heavier than an electron?  Give the number of protons in 17Cl35  What are Isobars? give any two examples  Name the particle which determines the mass of an atom.  What type of charge is present in the nucleus of an atom?  What was the model of an atom proposed by Thomson? How many elections at the maximum can be present in the first shell?  Name the Scientist & his experiment to prove that the nucleus of an atom is positively  charged. Define the following terms : (a) Atomic Number and (b) mass number. Write the charge on sub-atomic particles.  What are valence electrons? Give examples.  Symbol 16 S 32 states that- (1) the Atomic number of sulphur.  (2) electroni...

class 9th Physics practice sats

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                         Subject:- Physics (Work, Energy & Power) Description :-   Here you can see subjective questions for practice only. Section –A contains ‘work type questions’, section – B contains ‘energy type Questions & section –C contains ‘Power type Questions’ respectively. 1.        When is work said to be done? 2.        Define the SI Unit of work done. 3.        Define 1 Joule. 4.        State the reason, why work is a scalar quantity? 5.        Calculate the work done by a man rotating a wheel and an amusement slide a fair 40 times in one minute. 6.        Define: (a) Positive work done (b) Negative work done 7.        Give an example for each: (a)     Zero work ...

Force

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Force is like push or pull which can change the state of rest or of motion, or direction of motion of the body.  Appling the any force, body may be accelerate or retard the motion of a body. Force effects : It can change the shape & size of the body.  It can change the state of rest of a body.  It can bring a moving object to rest.  It can change the speed and direction of motion of a body.

Physical chemistry

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Electrolysis A process by which electric current is passed through a substance to effect a chemical change. The chemical change is one in which the substance loses or gains an electron (oxidation or reduction). The process is carried out in an electrolytic cell, an apparatus consisting of positive and negative electrodes held apart and dipped into a solution containing positively and negatively charged ions. The substance to be transformed may form the electrode, may constitute the solution, or may be dissolved in the solution. Electric current (i.e., electrons) enters through the negatively charged electrode (cathode); components of the solution travel to this electrode, combine with the electrons, and are transformed (reduced). The products can be neutral elements or new molecules. Components of the solution also travel to the other electrode (anode), give up their electrons, and are transformed (oxidized) to neutral elements or new molecules. If the substance to be tra...