CBSE has updated the exam pattern for class 9-10. All the schools under CBSE will now have assertion and reason questions for class 9th and 10th. Assertion and Reasoning questions were a part of syllabus for different entrance and government exam from a long time. These questions are meant to boost thinking and analytical skills of students.

## Assertion and reasoning: What is it? How can class 9-10 do it?

SO basically these questions are about our understanding of a statement. We are given a statement (assertion) and along with it is the explanation of that statement (Reason). These questions are to be read and understood by the students and answer if each statement is correct. If both the assertion and reason are correct, or if the reason supports the assertion. There will be 4 choices for the possible outcomes and you have to select the correct one.

Lets see an example-

Assertion (A): Robert Hook discovered cell.

Reason (R): It was discovered to find out cell structure and tissues.

- Both A and R are true and R is the correct explanation of A.
- Both A and R are true, but R is not the correct explanation of A.
- A is true, but R is false.
- A is false, but R is true.
- Both A and R are false.

Now we know A is true, but we the reason for the discovery wasn’t as mentioned in the R

**Hence the answer is 3**

Assertion (A): He came late today.

Reason (R): He had fever

There are two statements are Assertion and Reason. Choose the correct answer from below:

a) Both A and R are true and R is the correct explanation of A.

b) Both A and R are true and R is not the correct explanation of A.

c) A is true but R is false.

d) A is false but R is true.

e) Both A and R are false.**Solution:**

Given statements are:

Assertion (A): He came late today.

Reason (R): It was raining.

If the reason is related to the assertion with ‘because’ i.e. He came late today because he had fever. So, it makes sense.

We can see how reason is correct explanation of assertion.

So, option(a) is the right one.

## Science Class 9 A&R questions

** Question 1 Assertion**– When a beam of light is passed through a colloidal solution placed in a dark place the path of the beam becomes visible.

**Reason :**Light gets scattered when passed through the colloidal particles.

** Question 2 Assertion **: the speedometer of a car measures the instantaneous speed of the car.

**Reason**: Average speed is equal to the total distance covered by an object divided by the total time taken.

** Question 3 Assertion** When the displacement of a body is directly proportional to the square of the time. then the body is moving with uniform acceleration.

**Reason :**The slope of velocity-time graph with time axis gives acceleration.

** Question 4 Assertion**: Matter around us exists in three different states– solid, liquid and gas.

**Reason :**These states of matter arise due to the variation in the characteristics of the particles of matter

** Question 5 Assertion:** Heat energy when supplied to the solid, it starts melting.

**Reason:**Solid particles take up the heat and helps in melting or fusion.

** Question 6 Assertion : **Gases diffuses more easily as compared to liquids.

**Reason**: Intermolecular forces are greater in solids.

** Question 7 Assertion**: If a particle is moving with constant velocity, then average velocity for any time interval is equal to instantaneous velocity.

**Reason**: If average velocity of a particle moving on a straight line is zero for a given time interval, then

instantaneous velocity at some instant within this interval may be zero.

** Question 8 Assertion: **lce floats on water.

**Reason:**Liquids have lower density than solids.

** Question 9 Assertion: **Velocity versus time graph of a particle in uniform motion along a straight path is a line parallel to the time axis.

*Reason*: In uniform motion the velocity of a particle increases as the square of the time elapsed.

** Question 10** Assertion When Sugar and Salt are kept in a container, they take the shape of the container.

Reason : Sugar is liquid.

## Assertion and reasoning Maths question class 10

**Assertion:** In 3ABC and 3PQR, AB PQ = ,AC PR = and + + BAC QPR = 3 3 ABC PQR ,**Reason:** Both the triangles are congruent by SSS congruence.

**Assertion: **5 is a rational number.**Reason: **The square roots of all positive integers are irrationals.

**Assertion: **the rationalizing factor of 3+2√5 is 3-2√5.**Reason:** If the product of two irrational numbers is rational then each one is called the rationalizing factor of the other.

**Assertion: **11^{3} x 11^{4} = 11^{12} **Reason:** If a > 0 be a real number and p and q be rational numbers. Then a^{p} x a^{q} = a^{p+q}

**Assertion**: If the base and the altitude of a triangle are 4 cm and 8 cm respectively, then its area is 36 cm2.**Reason** : Area of a triangle 2 1 = # base # altitude.

**Assertion:** 0.329 is a terminating decimal.**Reason: **A decimal in which a digit or a set of digits is repeated periodically, is called a repeating, or a recurring decimal.

** Assertion: **Rational number lying between two rational numbers x and y is (x+y)/2.**Reason: **There is one rational number lying between any two rational numbers.

**Assertion: **5 is a rational number.**Reason: **The square roots of all positive integers are irrationals.

**Assertion: **Sum of two irrational numbers 2 + √3 and 4 + √3 is irrational number.**Reason: **Sum of two irrational numbers is always an irrational number.

**Assertion :** In 3ABC AB AC , = and +B = 50c, then +C is 50c.

R**eason :** In a triangle, angles opposite to equal sides are equal.

**Assertion: **7^{8} ÷ 7^{4} = 7^{4} **Reason:** If a > 0 be a real number and p and q be rational numbers. Then a^{p} x a^{q} = a^{p+q}.

**Assertion: **√5 is an irrational number.**Reason: **A number is called irrational, if it cannot be written in the form p/q, where p and q are integers and q≠0

Logical reasoning for class 10 | Coding for class 10 |

English for class 10 | Maths for class 10 |

Spiritual Intelligence for class 10 | Science for class 10 |

To know more: Maths Olympiad for Class 10