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Graphic representation of motion:

Graphs are used to represent the motion of an object. Graphs provide a convenient method to present basic information about a variety of events.

Examples of graphic representation of motion:

(i) In the telecast of a one-day cricket match.

(ii) Vertical bar graphs show the run rate of a team in each over.

(iii) As you have studied in mathematics, a straight line graph helps in solving a linear equation having two variables.

There are two major factors which can change in velocity.

(i) Changing in magnitude.

(ii) Changing in direction.

Differences between Speed and Velocity.

Speed: 

(i) It is a distance covered in unit time.

(ii) It is a scalar quantity. 

(iii) Average speed of moving object can not be zero. 

(iv) Speed of an object can never be zero. 

Velocity: 

(i) It is a displacement covered in unit time with direction. 

(ii) It is a vector quantity. 

(iii) Average velocity of moving object can be zero. 

(iv) Velocity of an object can be positive, negative or zero.  

The direction of motion along with its speed. The quantity that specifies both these aspects is called velocity.

Definition: Velocity is the speed of an object moving in a definite direction. It is called velocity.

S.I unit of velocity is m/s or m s^-1.

Type of Velocity:

(i) Uniform velocity: When an object covers equal displacement in equal time of interval. It is called uniform velocity. 

(ii) Non-uniform velocity: When a object covers unequal displacement in equal time of interval. It is called non-uniform velocity.  

(iii) Average velocity: Average velocity is given by the arithmetic mean of
initial velocity and final velocity for a given period of time.

Initial velocity : Initial velocity of an object means the velocity when the object starts displacing where time(t) may be zeto or t ≠ 0.

It is denrted by 'u'.

Final velocity : Final velocity of an object is given by time t. It is the value of final position in velocity of the object.

 Precautions undertaken before storing foodgrains are:                                                (i) Grains should be dried properly.                                                                             (ii) Proper chemical treatment should be done to protect grains from insects, pest and microorganisms. 

जर्मन तानाशाह एल्डोफ हिटलर अपने आम जन के बीच एक ऐसी विचार को आगे बढाया जिसमें सरकार की हर योजना मे पहल हो परंतु फिर वह योजना जनता-समाज की भागिदारी से चले | जिसके निम्नलिखित तत्व थे -

•  कट्टर जर्मन राष्ट्रवाद, 
• देशप्रेम, 
• विदेशी विरोधी, 
• आर्य और जर्मन हित 

इस विचार धारा के मूल अंग थे | वर्त्तमान में न तो हिटलर है और नहीं उसके नाज़ीवाद की विचारधारा | यह विचारधारा ही दुसरे विश्वयुद्ध का कारण बनी और हिटलर तानाशाह बना | उसने इस विचारधारा को कायम रखने के लिए लोगों पर बहुत जुल्म किये |