## Pradeep Kshetrapal is teaching live on Unacademy Plus

PHYSICS Class XI Pradeep Kshetrapal

Chapter 4. Motion in a plain VECTORS Lesson XI-4-1

Types of quantities in Physics Scalar-quantity or Scalar has magnitude. Does not need direction for its description. Example: Mass, length, time, volume, speed, temperature, work, energy, power, current, potential. In mathematical operations scalars follovw rules of ordinary algebra Pradeep Kshetrapal

Vector-quantity or Vector : a quantity which has both, magnitude and direction. Their description is not complete unless direction is specified Ex. Displacement, Area, velocity, acceleration, force, momentum, torque, magnetic moment. Vectors do not follow rules of mathematical operation of Algebra. They have their set of rules of mathematical operation for Vectors.

Notation of vector quantity. A scalar can be represented by a simple letter as in algebra. x. r (only magnitude) A vector is represented by a letter and an arrow above it. Ex. r(magnitude and direction) Some times it is also represented by Bold capital letter like A or R Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction . It is represented by an arrow sign The point at which vector acts or from where arrow starts is called origin or tail. Head of the arrow is called head or terminal point. Direction 360 degrees Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction . It is represented by an arrow sign. The point at which vector acts D Direction0 degrees or from where arrow starts is called origin or tai Head of the arrow is called head or terminal point. Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction . It is represented by an arrow sign The point at which vector acts or from where arrow starts is called origin or tail. Head of the arrow is called head or terminal point. Direction60 degrees Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction . It is represented by an arrow sign The point at which vector acts or from where arrow starts is called origin or tail. Head of the arrow is called head or terminal point. Direction 90 degrees Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction. It is represented by an arrow sign. The point at which vector acts or from where arrow starts is called origin or tail Head of the arrow is called head or terminal point. Direction 150 degrees Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction. It is represented by an arrow sign. The point at which vector acts or from where arrow starts is called origin or tail Head of the arrow is called head or terminal point. Direction 330 degrees Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Vector is a quantity which has magnitude and direction . It is represented by an arrow sign The point at which vector acts or from where arrow starts is called origin or tail. Head of the arrow is called head or terminal point. Direction 360 degrees Length of arrow represents its magnitude, the direction of arrow is direction of vector. Pradeep Kshetrapal

Definitions Equal vectors Equal vectors are those which have same magnitude (length) and same direction Pradeep Kshetrapal

Addition of vectors. Addition of two vectors depends on direction. The resultant (black) depends on the angle between vectors. Minimum value is A-B and maximum value is A+B 0 0 Pradeep Kshetrapal

Addition of vectors. Addition of two vectors depends on direction. The resultant (black) depends on the angle between vectors. Minimum value is A-B and maximum value is A+B 30 8 N, 0 6 N, 3013.5 N, 12.8 Pradeep Kshetrapal

Addition of vectors. Addition of two vectors depends on direction. The resultant (black) depends on the angle between vectors. Minimum value is A-B and maximum value is A+B 210 8 N, 0 + 6 N, 2104.1 N, 313. 1 Pradeep Kshetrapal

Addition of vectors. Addition of two vectors depends on direction. The resultant (black) depends on the angle between vectors. Minimum value is A-B and maximum value is A+B 240 8 N, 0 + 6 N, 2407.2 N, 313.9 Pradeep Kshetrapal

Addition of vectors. Addition of two vectors depends on direction. The resultant (black) depends on the angle between vectors. Minimum value is A-B and maximum value is A+B 300 8 N, 0 +6 N, 3002.2 N, 334.7 Pradeep Kshetrapal

Addition of vectors. Addition of two vectors depends on direction. The resultant (black) depends on the angle between vectors. Minimum value is A-B and maximum value is A+B 8 N, 0 + 6 N, 36014 N, 0 Pradeep Kshetrapal

Addition : Triangle method-another example Second vector is moved such that its tail coincide with head of the first vector. Then a vector from tail of first to head of second gives resultant vector, or addition of two. Adding 2 Vectors

Addition effects in x and y direction To Add 2 Vectors Numerically 15(5,14) 15 10 10 5 7,4)

Addition by parallelogram Two vectors A and B of magnitude a and b, inclined at angle are acting at a point O. If these vectors are represented by two sides of a parallelogram then resultant i.e. addition is represented by the diagonal passing through O. R ABO The magnitude of this resultant is equal to r, the length of OQ which is equal to rON+ ON2 a sine M a cose N If a is the angle made by resultant then it is given by relation -OM MN +20M.MN +QN MMN2 2OM.MN +QN tan b acose Pradeep Kshetrapal

Components of a vector, Vector B is | effective in both axis the directions. Its effect in x direction is given X-akis by Bx. And |effect in Y direction is given by By Pradeep 6a comp.avi

Component Effect of a vector in a particular rection Magnitudes Ar Pradeep Kshetrapal

Order no matter Five vectors are added in different order. Result by each method is same. Addition of five vectors: A+ B D+ E C+B Pradeep Kshetrapal

Order no matter Five vectors are added in different order. Result by each method is same. Addition of five vectors: adog obetrgeiA+B+C D+E+A C+B+A

Wind effecting airplane, add vectors Tailwind Headwind Crosswind velocity Twelocity |Resultan VelocityVelocity AiroplanWind Pradeep Kshetrapal

Wind effecting airplane add vectors Tailwind Headwind Crosswind velocity Twelocity |Resultan VelocityVelocity AiroplanWind Pradeep Kshetrapal

Wind effecting airplane add vectors Tailwind Headwind Crosswind Velocity Twelocity |Watan VelocityVelocity Resultan AiroplanWind Pradeep Kshetrapal

Adding vectors, river and boat Motion of Riverboat With Current Motion of River boat Without Current Pradeep Kshetrapal

Adding vectors, river and boat Motion of Riverboat With Current Motion of River boat Without Current Pradeep Kshetrapal

Add Horizontal and vertical velocity of the bomb Pradeep Kshetrapal

Add Horizontal and vertical velocity of the bomb Pradeep Kshetrapal

Add Horizontal and vertical velocity of the bomb Pradeep Kshetrapal

Projectile under gravity Pradeep Kshetrapal

Projectile under gravity Pradeep Kshetrapal

Projectile under gravity Pradeep Kshetrapal

Projectile under gravity Vertical free fall Gravity- free path Pradeep Kshetrapal

Horizontal projectile t- s miS Pradeep Kshetrapal

Horizontal projectile t-9.0s 100 m/s Yy- 90 m/s Pradeep Kshetrapal

Non Horizontal projectile Ty m/s Vy=--m/s m/s Pradeep Kshetrapal

Non Horizontal projectile t 14.0s 60m/s vy=-80 m/s Tx= Pradeep Kshetrapal

Ball observed from moving truck and ground Pradeep Kshetrapal

Ball observed from moving truck and ground Pradeep Kshetrapal

Maximum range 30 45 60 Pradeep Kshetrapal

Maximum range 30 45 60 Pradeep Kshetrapal

Maximum range 30 45 60 Pradeep Kshetrapal

Maximum range 30 45 60 Pradeep Kshetrapal

Monkey and Zookeeper If there is no gravity, and Banana is thrown aiming monkey ) Pradeep Kshetrapal

Thrown above monkey, Gravity present Pradeep Kshetrapal

Thrown above monkey, Gravity present Pradeep Kshetrapal

Aiming monkey, throw fast Pradeep Kshetrapal

Aiming monkey, throw fast 2 Pradeep Kshetrapal

Aiming monkey throw slow Pradeep Kshetrapal

Aiming monkey throw slow Pradeep Kshetrapal