Title PHYSICS PART- 1.pdf ✅

PHYSICS Class - C3 (Part - I) 1 VECTORSWISE UP Physical Quantity : A Quantity which can able to measure is known as Physical Quantity. Types of Physical Quantities • Fundamental Physical Quantities • Derived Physical Quantities • Scalar Physical Quantities • Vector Physical Quantities Fundamental physical quantities : The physical quantities which do not depend on any other physical quantities for their measurements are known as fundamental physical quantities.
Ex: Mass, Length, Time etc... Derived physical quantities : The physical quantities which depend on any other physical quantities for their measurements are known as Derived physical quantities. Ex: Speed, Acceleration, Force etc... Scalar physical quantities : The physical quantities having magnitude are known as scalar physical quantities. Ex: Distance, Speed, Electric current etc.... Magnitude of a physical quantity is the numerical value followed by a unit. Ex: Mass = 5 kg, Change in speed = 3 m/s Vector physical quantities: The physical quantities having both magnitude and direction and also obeys rules of vector algebra are known as vector physical quantities. Ex: velocity, Acceleration, Impulse etc... Differences between Scalar and Vector Quantities Scalar Quantities Vector Quantities 1. They are expressed in magnitude only. 1. They are expressed in magnitude as well as direction. 2. They can be added by simple arthemetic means 2.They cannot be added by simple arthe metic means.
3. They cannot be easily plotted on graph paper. 3. They can be easily plotted on graph paper. CONCEPT - I INTRODUCTION TO SCALARS AND VECTORS, TYPES OF VECTORS Based on the mathematical behaviour, physical quantities are classified into various types. Among them we are going to discuss two categories based on their importance in dealing with physical quantities. They are 1. Scalar physical quantities. 2. Vector physical quantities Scalar Physical Quantities : Physical quantity that follows simple algebra is called scalar physical quantity or simply 'Scalar' Ex : Length, Mass, Time etc....; The statement of a scalar consists of its magnitude along with a proper algebraic sign. Magnitude of a physical quantity is the numerical value followed by a unit. Ex : i) Mass = 5Kg ii) Change in speed = 3 m/s Vector Physical Quantities : A physical quantity which follows the vector law of addition and with a specified direction is called vector physical quantity or simply
'Vector' Vector has both magnitude and direction. Ex: Displacement, velocity, magnetic field induction etc. Representation of a vector quantity : A vector is denoted using an alphabet over headed with an arrow a⃗ Ex: If A is the origin and B is the terminus, then the vector is expressed as • The magnitude of a vector is denoted as |a⃗| (or) a. • The magnitude of a vector is a scalar. > Types of vectors : 1) Like vectors : The vectors which have same direction are called 'like vectors' 2) Unlike vectors : The vectors which are mutually opposite are called 'Unlike vectors'