VIDEO 6

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BASIC MATHEMATICS

Till now covered• Units and dimensions

Till now covered• Units and dimensions• Dimensional analysis

Till now covered• Units and dimensions• Dimensional analysis• Significant figures

Till now covered• Units and dimensions• Dimensional analysis• Significant figures• Least count

Till now covered• Units and dimensions• Dimensional analysis• Significant figures• Least count• Error analysis

Important concepts

Important concepts• Knowledge of same basic graphs , like equation of line y = m.x + c , quadratic equations

etc.

Important concepts• Knowledge of same basic graphs , like equation of line y = m.x + c , quadratic equations

etc.• Basic knowledge of trigonometry.

Important concepts• Knowledge of same basic graphs , like equation of line y = m.x + c , quadratic equations

etc.• Basic knowledge of trigonometry.• Vectors

Important concepts• Knowledge of same basic graphs , like equation of line y = m.x + c , quadratic equations

etc.• Basic knowledge of trigonometry.• Vectors • Calculus basics

Cover two topicsWe cover two topics for now First :VECTORS

Cover two topicsWe cover two topics for now First :VECTORSThen Later:CALCULUS

Vectors (type of physical quantity)

DEFINITION SCALARS Quantities in physics which are

determined uniquely by one number are called scalars.

Example:Mass , temperature , distance , speed , time ,

work , energy.

DEFINITION VECTORSQuantities in physics which are determined

completely by two things 1st -> Magnitude2nd ->Direction are called vectors.Example: weight , force ,acceleration ,velocity, displacement .

Don’t Get Confused• Physics and English Dictionary are Different.• Mass , Weight ho ya speed ,velocity • Both means same in English dictionary.

BUT• In PHYSICS both have completely DIFFERENT Meanings.

To Understand VectorsTo understand vectors we will consider examples

of vectors for easy understanding.

Pehla concept hai Distance/Displacement ka.

Doosra concept hai speed/velocity.

Easiest thing to measure in a body :“ ITS POSITION WITH TIME “

Position is calculated with some reference point always .

Reference point is called ORIGIN.

3 Types of motion

1-dimensional motion. 2-dimensional motion. 3-dimensional motion.

1-D Motion 1-Dimensional motion means:• body only moves along a line.• only one number good enough to represent a

position uniquely.• one single axes used to represent it.Simplest Example:

“ Motion Of a Freely Falling Ball “

Motion of ball

Three positions during fall

Reference point dependence If top is reference point then initial value of position is 0 final value of position is -H

Reference point dependence If middle is reference point then initial value of position is H/2 final value of position is -H/2

Reference point dependence If ground is reference point then initial value of position is H final value of position is 0

THREE CASES

2-D Motion2 –dimensional motion means:• Body moves on a plane.• There are 2 numbers needed to specify a

unique position.• 2 perpendicular axes used to represent it.

• 2²=4 quadrants made by axes

Representation of positions on 2D

3-D Motion 3 dimensional motion means :• Body moves in space.• There are 3 numbers needed to specify a unique position.• 3-perpendicular axes used to represent it.

• 2³ = 8 octants made by axes.

3 axes, 3 numbers used to represent

Example of a CUBE

SAY A FLY MOVES IN CUBETHENFly’s position will always be (at any time)

determined uniquely by 3 numbers ( x,y,z).WHERE 0<x<1 , 0<y<1, 0<z<1 So here motion of fly is 3 dimensional

SO THESE WERE 3 TYPES OF POSSIBLE MOTION:

NEXT:

We further understand vectors.

Taking distance /displacement ,speed /velocity as examples in next video

• Abhi ke liye good bye…..