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  Question Bank – Laws of Motion 1. Very Short Answer Questions (1 Mark) State Newton’s first law of motion. Answer : An object remains at rest or in uniform motion in a straight line unless acted upon by an external force. What is inertia?

  Question Bank – Work, Energy, and Power 1. Very Short Answer Questions (1 Mark) Define work. Answer : Work is said to be done when a force is applied to an object, and the object displaces in the direction of the applied force. What is the SI unit of work? Answer : Joule (J). State the condition for work to be zero.

Question Bank – Gravitation 1. Very Short Answer Questions (1 Mark) What is the value of the universal gravitational constant (G)? Answer : 6.674 × 1 0 − 11   Nm 2 / kg 2 6.674 \times 10^{-11} \, \text{Nm}^2/\text{kg}^2 6.674 × 1 0 − 11 Nm 2 / kg 2 State Newton’s law of gravitation. Answer : Every particle in the universe attracts every other particle with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between them.

1. Position and Displacement: Position: Location of an object relative to a reference point. Displacement: Change in position; includes direction and magnitude.

Kinematics is the branch of physics that studies the motion of objects without considering the forces causing that motion. It's the science of describing and analyzing the motion of objects, including their position, velocity, and acceleration, without delving into the forces that produce that motion. By focusing solely on the motion itself, kinematics provides a fundamental framework for understanding various physical phenomena, from the motion of planets and stars to the movement of atoms and particles.

Chapter: Units and Measurements Topic: Dimensions and Dimensional Analysis 1. Dimensions of Physical Quantities Dimensions of a physical quantity are the powers to which the fundamental units (base quantities) must be raised to represent that quantity. 1.1 Fundamental Quantities and Their Dimensions

 The International System of Units (SI), also known as the metric system, is the modern form of the metric system and the most widely used system of measurement worldwide. It provides a standardized framework for measuring physical quantities, ensuring consistency and precision across scientific, industrial, and everyday applications. The SI system is maintained by the International Bureau of Weights and Measures (BIPM) and has undergone significant historical developments and refinements since its inception. Historical Developments Origins

  Physical quantities are properties or characteristics of physical systems that can be measured and quantified. They describe the fundamental aspects of the physical world and are essential for understanding, analyzing, and predicting physical phenomena. Physical quantities can be classified into two main categories: fundamental quantities and derived quantities. Fundamental Quantities Fundamental quantities are basic physical properties that are considered independent and are not derived from other quantities. In the International System of Units (SI), there are seven fundamental quantities: Length  (meter, m) Mass  (kilogram, kg) Time  (second, s) Electric Current  (ampere, A) Thermodynamic Temperature  (kelvin, K) Amount of Substance  (mole, mol) Luminous Intensity  (candela, cd) These fundamental quantities form the foundation for defining all other physical quantities. Derived Quantities Derived quantities are physical properties that are de...

 Measurement is fundamental to numerous aspects of science, technology, industry, and daily life. Here are key reasons why measurement is essential: 1. Standardization and Consistency:    Measurement provides a standardized way of quantifying physical quantities. This standardization ensures that measurements are consistent and comparable across different contexts, locations, and times. Without standardized measurements, it would be impossible to replicate experiments, compare results, or establish reliable benchmarks. 2. Scientific Exploration and Discovery:    Measurement is the backbone of scientific research and experimentation. It allows scientists to quantify observations, test hypotheses, and develop theories. Accurate measurements enable researchers to validate their findings, ensuring that results are reliable and can be reproduced by others. 3. Technological Development:    Technological advancements rely heavily on precise measurements. Engi...

Measurement is the process of quantitatively comparing a physical quantity to a predefined standard unit. It involves determining the size, amount, or degree of a particular physical quantity by using instruments or tools that provide a numerical value. This numerical value is expressed in units that are consistent and standardized, allowing for accurate and precise communication of the quantity being measured. Measurement is essential in science, engineering, and everyday life because it provides a way to quantify observations and phenomena, making it possible to analyze, compare, and replicate results. For example, measuring the length of an object involves comparing it to a unit of length, such as a meter or a centimeter, using a ruler or a measuring tape. There are several key aspects to consider in measurement: 1. Quantity to be Measured: This is the physical property or attribute that is being measured, such as length, mass, time, temperature, or volume. 2. Unit of Measurement: ...

 Welcome to the fascinating world of physics! As you embark on this journey through the first chapter, "Physical World and Measurement," you are stepping into a realm where the laws of nature unfold in all their elegance and complexity. This chapter serves as the foundation upon which the entire edifice of physics is built, and it is here that you will begin to appreciate the profound ways in which physics helps us understand the universe. Physics is not just a subject; it is the language through which we decode the mysteries of the cosmos. From the tiniest subatomic particles to the vast expanse of galaxies, physics provides the principles and tools that allow us to explore and comprehend the nature of reality. In this chapter, you will discover the fundamental concepts that define the physical world and the precise methods of measurement that enable us to quantify and analyze it. As you delve into this chapter, consider the great physicists who have come before you—Galileo,...

Welcome, budding physicists, to our dedicated blog for CBSE Class XI Physics ! As you embark on this fascinating journey through the 2024-25 academic year, get ready to explore the wonders of the universe through the lens of Physics. This blog aims to be your trusted companion, providing you with insightful explanations, helpful study tips, and engaging content that aligns with the CBSE curriculum. Physics is not just a subject; it's a way to understand the natural phenomena that govern our everyday lives. From the motion of celestial bodies to the principles that power our modern technology, Physics offers profound insights into how the world works. This year, you will delve into a range of exciting topics, including: 1. Physical World and Measurement: Understand the fundamental concepts that form the basis of all physical sciences. Learn about the importance of measurement and the role of units and dimensions. 2. Kinematics: Explore the motion of objects, and get to grips with c...