Maths is not a subject , it is a habit like our daily activities eating , sleeping and many more. As per my experience which students deal it as a game or fun as their habit , after aomestime they become champion for it . I have seen there are two type of students 1. Who take it as their habit , after some they become champion 2. Who take it as a subject , they always try to deal it as other subjects and they finds several difficulties to raise their logical power by this subhects.   So it is my best suggestion for students to death this subject as a habit , for that they should solve problems at least one hour every  day which can make them as a champion in maths....

Endothermic reaction : Any chemical reaction that absorbs heat from the environment is termed as an endothermic reaction. The absorbed energy provides the activation energy for the reaction to occur.

Example : Mixing water ( H2O ) with Potassium Chloride ( KCl ) is an example of endothermic reaction.

Photosynthesis is also an example of endothermic reaction. Here Chrolophyll is used from sunlight to react water and carbon dioxide ( CO2 ) to make Glucose and Oxygen ( O2 ).

Note : Endothermic reaction results in cooling of environment.

Exothermic reaction : Any chemical reaction that releases heat to the environment in the form of heat or light is termed as exothermic reaction. Exothermic reactions may be warm or explosive.

Example : Any combustion reaction, respiration , rusting of iron etc are some of the examples of exothermic reaction. In these cases heat is released as a result of exothermic reaction.

Note : Exothermic reaction is exactly the opposite of endothermic reaction.

Newton's Universal Law of Gravitation states that

Any two objects exert a gravitational force of attraction on each other.

The direction of the force is along the line joining the objects. 

The magnitude of the force is proportional to the product of the gravitational masses of the objects and inversely proportional to the square of the distance between them.

F=GMmr2">F

=GMm/r^2

where F">F represents the force in Newtons, 

M">M and m">m represent the two masses in kilograms,

and r">r represents the separation in meters. 

G">G represents the gravitational constant, which has a value of 6.674⋅10−11N(m/kg)2">6.674*10^−11N(m/kg)^2.

Because of the magnitude of G">G, the gravitational force is very small unless large masses are involved.

WRITING CHEMICAL FORMULA-

*The Chemical Formula is a representation of a substance [element or compound] by means of the symbol.                                             THE RULES FOR WRITING CHEMICAL FORMULA ARE-

*The Symbol Of the elements ^should be known.

*The Valency of the elements should be known. 

SOME ELEMENTS WITH POSITIVE AND NEGATIVE VALENCIES-

+VE VALENCY    ELEMENT  SYMBOL   ION

V-1                     Potassium    K              K¹⁺

                           Sodium           Na            Na¹⁺

V-2                     Calcium          Ca            Ca²⁺

                          Magenisum     Mg           Mg²⁺

V-3                    Aluminium       Al             Al³⁺

-VE VALENCY    ELEMENT    SYMBOL    ION

V-1                   Chlorine           Cl                Cl^1-

                          Bromine           Be               Br^1-

V-2                    Oxide                O                O^2-

                          Sulphide           S                 S^2-

V-3                    Phosphate      Po_{4                PO4^3-}

Jobs. 

Isn't everything about getting a job done? 

It could be something you have already done, but wonder if it could have been done differently. Or it could be something you need to do and wonder how to go about doing it. You fumble and hesitate, and struggle to express a situation imagined to be the best for you. How do you put something so complicated into words without making mistakes? 

Conditional tenses can be tricky that way, but the pattern once grasped makes it easy as ABC. 

Let's look at some relatable examples, shall we? 

You go to a cafe and order your favourite coffee. As you curl up with it on a cosy sofa, you think about how the coffee could affect your studying at night. 

If I drink (Present)this coffee, I won't study(Present ) tonight. 

You haven't ordered your coffee yet and are beginning to regret the thought of having it, because:   

  If I drank (Simple Past) this coffee, I wouldn't study (Present Conditional) tonight. 

You end up ordering a chocolate shake, because:

 If I had drunk (Past Perfect) this coffee, I wouldn't have studied (Present Perfect conditional) tonight. 

Easy? Now follow these additional tips to ensure that you do it right all the way:

• For sentences that are true, apply zero conditional tenses:     If you heat (Present) water at 100 degrees, it boils (Present).
• To express a present condition based on a past imagined differently, use the format of If clause+ past perfect+ present conditional.  If you hadn't called (Past perfect) me, I would be sleeping (present continuous conditional) peacefully at home. 
• To express a past condition based on current or ongoing activity, use this format: If clause+ simple past+ present perfect conditional. 

If I were (simple past) good in drawing, I would have completed (present perfect conditional) your assignment. 

precision = It is defined as the repetitiveness of a result is known as precision.
Example- The standard value of frequency in India is 50hz during the experiment of 10 time you are getting result of 46,46.5,46,45.5,46,46,46,49,46,46
result 46 is the precision result
Accuracy- Closeness toward the standard result is known as accuracy
49 is accurate but not precise