Thursday, June 23, 2022

The Smart Teacher

Problem : The price of 3 buckets and 5 mugs is ₹ 100 and the price of 5 buckets and 2 mugs is ₹ 970. Find the price of one bucket and one mug separately. Solution : Suppose that the price of one bucket is ₹ x and price of one mug is ₹ y. therefore, the price of 3 buckets and 5 mugs = 3x+5y ₹ According to the first condition ₹ 3x+5y =1000 3x+5y = 1000 ............1 and price of 5 buckets and 2 mugs = ₹ 5x+2y According to the second condition ₹ 5x+2y = 970 so, 5x+2y = 970 ............2 Multiply by 5 both sides of the question 1 and by 3 in both sides of thr questio 2. 15x+25y = 5000 ..........3 15x+6y = 2910 ............4 Subtracting question 4 from the question 3 19y = 2090 y = 2090/19 or, y =110 Substituting the value of y in question 1 3x+5y = 1000 3x+ 5×110 = 1000 or, 3x+550 = 1000 3x = 1000-550 3x = 450 x = 450/3 x = 150 Hence price of one bucket = ₹ 150 and price of one mug = ₹ 110

Monday, May 16, 2022

रासायनिक अभिक्रिया के भेद -

 रासायनिक अभिक्रिया के प्रकार निम्न आधार पर हैं -

1. अवस्था परिवर्तन के आधार पर

2. अभिक्रिया की दिशा परिवर्तन के आधार पर

3.ऊष्मा के अवशोषण व निष्कासन के आधार पर

अवस्था परिवर्तन के आधार :-

                                       इसके आधार पर अभिक्रिया निम्न प्रकार की होती हैं :

1. संयोजन/ योगात्मक अभिक्रिया

2. वियोजन/अपघटन अभिक्रिया

3. विस्थापन अभिक्रिया

4. द्वि- विस्थापन अभिक्रिया

5. उपचयन अभिक्रिया

6.अपचयन अभिक्रिया

अभिक्रिया की दिशा के परिवर्तन के आधार पर :

1. उत्क्रमणीय अभिक्रिया

2. अनुत्क्रमणीय अभिक्रिया

ऊष्मा के अवशोषण व निष्कासन के आधार पर :

1. ऊष्माक्षेपी अभिक्रिया

2. ऊष्माशोषी अभिक्रिया

Friday, May 13, 2022

Question related to age

 Example : Before 5 years, the age of father was thrice the age of his son. After 10 years, the age of father will be twice the age of his son. Find the present ages of father and son.

Say that the present age of father is x years and the age of son is y years.

The age of father before 5 years = (x-5) years

The age of son before 5 years = ( y-5) years

The age of father after 10 years = (x+10) years

The age of son after 10 years = (y+10) years

According the first condition,

x-5 =3(y-5) 

x-5=3y-15

x-3y=-10  .................(1)

According the second condition,

x+10=2(y+10)

x+10=2y+20

x-2y=10 .................(2)

Solving question (1) and (2),

x=50 ,y=20

Therefore,

Father's present age = 50 years and

Son's present age = 20 years

विस्थापन अभिक्रिया की परिभाषा

 विस्थापन/प्रतिस्थापन अभिक्रिया :-

                                                जिस अभिक्रिया में अधिक क्रियाशील पदार्थ , कम क्रियाशील को हटाकर स्वयं यौगिक के साथ जुड़ जाता है, तो इस प्रकार की अभिक्रिया को विस्थापन अभिक्रिया कहते हैं।