Last Updated on August 5, 2024 by XAM CONTENT
Hello students, we are providing assertion and reason questions for class 11 physics. Assertion reason questions are the new question format that is introduced in CBSE board. The resources for assertion reason questions are very less. So, to help students we have created chapterwise assertion reason questions for class 11 physics. In this article, you will find assertion reason questions for CBSE Class 11 Physics Chapter 3 Motion in a Straight Line.
| Chapter | Motion in a Straight Line |
| Type of Questions | Assertion Reason Questions |
| Nature of Questions | Competency Based Questions |
| Board | CBSE |
| Class | 11 |
| Subject | Physics |
| Unit | Unit 2 Kinematics |
| Useful for | Class 11 Studying Students |
| Answers provided | Yes |
| Difficulty level | Mentioned |
| Important Link | Class 11 Physics Chapterwise Assertion Reason |
Assertion Reason Questions on Motion in a Straight Line
Directions:
For below questions, two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) are as given below.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false and R is also false.
Q. 1. Assertion: In real-life, in a number of situations, the object is treated as a point object.
Reason: An object is treated as point object, as far as its size is much smaller than the distance, it moves in a reasonable duration of time.
Difficulty Level: Medium
Ans. Option (a) is correct.
Explanation:
The approximation of an object as point object is valid only, when the size of the object is much smaller than the distance it moves in a reasonable duration of time.
Therefore, both A and R are true and R is the correct explanation of .
Q. 2. Assertion: If the displacement of the body is zero, the distance covered by it may not be zero.
Reason: Displacement is a vector quantity and distance is a scalar quantity.
Difficulty Level: Medium
Ans. Option (b) is correct.
Explanation:
Distance is the total path length travelled by the object. But displacement the shortest distance between the initial and final positions of the object. So, distance can never be negative or zero. But displacement can be zero, positive and negative.
Also, distance is a scalar quantity. It means that, it is always positive but however displacement is a vector quantity. So, it may be positive, zero or negative depending on given situation.
Therefore, both A and R are true but R is not the correct explanation of A.
Q. 3. Assertion: An object can have constant speed but variable velocity.
Reason: SI unit of speed is m/s.
Difficulty Level: Medium
Ans. Option (b) is correct.
Explanation:
Velocity is a vector quantity, so it has both direction and magnitude. Hence, an object can have variable velocity by keeping its magnitude constant, i.e. speed and by changing direction only.
The SI unit of speed is m/s.
Therefore, both A and R are true but R is not the correct explanation of A .
Q. 4. Assertion: The speed of a body can be negative.
Reason: If the body is moving in the opposite direction of positive motion, then its speed is negative.
Difficulty Level: Medium
Ans. Option (d) is correct.
Explanation:
Speed can never be negative because it is a scalar quantity. So, if a body is moving in negative direction, then also the speed will be positive.
Therefore, A is false and R is also false.
Q. 5. Assertion: For motion along a straight line and in the same direction, the magnitude of average velocity is equal to the average speed.
Reason: For motion along a straight line and in the same direction, the magnitude of displacement is not equal to the path length.
Difficulty Level: Medium
Ans. Option (c) is correct.
Explanation:
For motion in a straight line and in the same direction,
Displacement = Total path length
Average velocity = Average speed
Therefore, A is true but R is false.
Also check
- Motion in a Straight Line Class 11 Assertion Reason Questions Physics Chapter 3
- Units and Measurements Class 11 Assertion Reason Questions Physics Chapter 2
Topics from which assertion reason questions may be asked
- Elementary concepts of differentiation and integration for describing
- Motion, uniform and non- uniform motion, average speed and instantaneous velocity
- Uniformly accelerated motion
- Velocity – time and position-time graphs.
- Relations for uniformly accelerated motion
If the position of an object does not change w.r.t. its surrounding with the passage of time, it is said to be at rest. e.g. Book lying on the table, a person sitting on a chair, etc.
If the position of an object is continuously changing w.r.t. its surrounding w.r.t time, then it is said to be in the state of motion. e.g. The crawling insects, water flowing down a dam, etc.
The process of measurement is basically a comparison process. To measure a physical quantity, we have to find out how many times a standard amount of that physical quantity is present in the quantity being measured. The number thus obtained is known as the magnitude and the standard chosen is called the unit of the physical quantity.
You are going to study the above topics in class 11 Motion in a Straight Line chapter. So, assertion reason questions based on above topics may be asked.
We hope the given Assertion and Reason Questions for Motion in a Straight Line Class 11 Physics helps you in your learning.
Frequently Asked Questions (FAQs) on Motion in a Straight Line Assertion Reason Questions
Q1: What are assertion-reason questions?
A1: Assertion-reason questions consist of two statements: an assertion (A) and a reason (R). The task is to determine the correctness of both statements and the relationship between them. The options usually include:
(i) Both A and R are true, and R is the correct explanation of A.
(ii) Both A and R are true, but R is not the correct explanation of A.
(iii) A is true, but R is false.
(iv) A is false, but R is true. or A is false, and R is also false.
Q2: Why are assertion-reason questions important in Physics?
A2: Assertion-reason questions are important in Physics because they test not only the factual knowledge of students but also their understanding of the concepts and the ability to relate different pieces of information. They encourage critical thinking and deeper comprehension of the subject matter.
Q3: How can practicing assertion-reason questions help students?
A3: Practicing assertion-reason questions can help students in several ways:
Improved Conceptual Understanding: It helps students to better understand the concepts by linking assertions with their reasons.
Enhanced Analytical Skills: It enhances analytical skills as students need to critically analyze the statements and their relationships.
Better Exam Preparation: These questions are asked in exams, and practicing them can improve your performance.
Q4: What strategies should students use to answer assertion-reason questions effectively?
A4: Students can use the following strategies:
Understand Each Statement Separately: Determine if each statement is true or false independently.
Analyze the Relationship: If both statements are true, check if the reason correctly explains the assertion.
Q5: What are common mistakes to avoid when answering Assertion-Reason questions?
A5: Common mistakes include:
Not reading the statements carefully and missing key details.
Assuming the Reason explains the Assertion without checking the logical connection.
Confusing the order or relationship between the statements.
Overthinking and adding information not provided in the question.
Q6: What resources can help me practice Assertion-Reason questions?
A6: Use study guides specifically designed for Assertion-Reason questions. Online educational platforms and reference books for Class 11 Physics also offer practice questions and explanations. xamcontent.com also provides assertion reason questions for cbse class 11 physics.
Q7: Explain the different types of motion on the basis of path followed.
A7: On the basis of the nature of path followed, motion is classified as
Rectilinear Motion: The motion in which a particle moves along a straight line is called rectilinear motion. e.g. Motion of a sliding body on an inclined plane.
Circular Motion: The motion in which a particle moves in a circular path is called circular motion. e.g. A string whirled in a circular loop.
Oscillatory Motion: The motion in which a particle moves to and fro about a given point is known as oscillatory motion. e.g. Simple pendulum.
Q8: Explain the different types of motion on the basis of number of coordinates required.
A8:
One-dimensional Motion (1-D): The motion of an object is considered as 1-D, if only one coordinate is needed to specify the position of the object.
Two-dimensional Motion (2-D): The motion of an object is considered as 2-D, if two coordinates are needed to specify the position of the object. In 2-D motion, the object moves in a plane. e.g. A satellite revolving around the earth.
Three-dimensional Motion (3-D): The motion of an object is considered as 3-D, if all the three coordinates are needed to specify the position of the object.
This type of motion takes place in three-dimensional space.
e.g. Butterfly flying in garden, the motion of water molecules and motion of kite in the sky.
