Class 11 Physics Revision Notes for Chapter 3 – Motion in a Straight Line
Learning Physics involves regular practice just like other subjects. Students often find Class 11 Physics to be challenging due to the complex terms, equations and laws in the chapters. To properly understand the topics, it is crucial for students to be familiar with the fundamental formulas and to regularly solve problems.
CBSE Class 11 Physics Notes of Chapter 3 present complete information about the subject in a way that is brief and simple to understand. Extramarks offers concise, easily readable Class 11 Physics Chapter 3 Notes to aid students in revising the key topics before examinations.
1. Mechanics:
The study of how physical objects move is covered in the branch of physics known as mechanics.
It can be broadly divided into the branches below:
- Statics: This area of mechanics deals with the study of physical objects in a state of rest.
- Kinematics: This branch of mechanics studies how physical objects move without taking the causes of that movement into account.
- Dynamics: This branch of mechanics studies how physical objects move while taking the causes of that movement into account.
2. Rest And Motion
- Rest:
When an object maintains its position in relation to its surroundings, it is said to be at rest.
For instance, the whiteboard in a classroom is at rest with regard to the classroom.
- Motion:
When an object shifts in relation to its surroundings, it is said to be in motion.
For instance, when we move relative to the ground while walking, running or riding a bike, we are said to be in motion.
- Rest and Motion are Relative:
Motion and rest depend on the observer. The same object might be in motion in one situation while it might be at rest in another.
For instance, the driver of a moving car is at rest in relation to a man (an observer) sitting in the passenger seat but is in motion in relation to an observer standing on the ground.
3. While Studying This Chapter:
- The objects would be regarded as point mass objects.
- If an object moves over distances that are significantly greater than its own size, it can be considered to have a point mass.
- We could limit our research to the study of rectilinear motion, or the movement of objects in straight lines.
4. Position, Distance, Displacement:
Position: An object’s position is always expressed in relation to some reference point, known as the origin. We take into account two physical quantities to express the change in position.
Distance: This is the actual path that an object travels while in motion. Its dimensions are [M0L1 T0] and its S.I. unit is ′m′.
Displacement: This term describes the variation between the final and initial positions of an object during motion.