2. What is Motion
• An object is said to be in motion if it continuously changes its position with
time.
• Motion is change in position of an object over time
• For ex: A moving train in motion because its position changes with time.
3. Types of Motion
Some objects move in a straight line while others may move in a curved path.
Some objects may rotate, and others may oscillate. Some may have
combination of these.
4. Linear Motion
• If an object is continuously moving in a straight path than it is said to be in
linear motion
• For example - A car moving in a straight path.
5. Uniform Motion
If a body covers equal distance in a regular interval of time than motion is said
to be in uniform motion.
Example: A car moving at a constant speed.
6. Non-Uniform Motion
• If a body covers unequal distances in equal interval of time than it is said to
be in uniform motion.
• Example: A car moving on a crowded street.
7. Distance and Displacement
• Distance is the total path length covered by an object . Its SI unit is meter
• It is scalar quantity.
• On the other hand, Displacement is the shortest distance covered by initial
and final positions of the body. Its SI unit is meter.
• It is vector quantity.
8. Speed
Speed is defined as distance covered by body per unit time. It is a scalar quantity.
Its SI unit is m/s
The Mathematical formula of speed is :- Distance
Time
A body travelling from one place to another might slow down, stop, speed up or
move at constant speed. So that’s where average speed comes handy.
The mathematical formula of average speed is :- Total distance
Total Time
9. Velocity
Velocity is defined as displacement covered per unit time. It is a vector quantity.
Its SI unit is m/s
The mathematical formula of velocity is :- Displacement
Time
A body moving from one point to another may change its velocity many times. But
have an average velocity of its journey.
The mathematical formula of average velocity is Initial + Final Velocity
Time
10. Acceleration
Acceleration is defined as rate of change in velocity. It is a vector quantity.
Its SI unit is m/s^2
The mathematical formula of acceleration is :- Change in velocity
Time Taken
11. Equations of Motion
• There are three equations of motion :-
• Velocity time relation :- v = u + at
• Position Time Relation :- s = ut +1 at^2
• 2
• Velocity Position Relation :- v^2 – u^2 = 2as
12. Uniform Circular Motion
• When an object moves in a circular path at uniform speed, its motion is
known as uniform circular motion.
• Its Mathematical Formulae is :- v = 2πr
t
For Example :- A satellite moving around the earth.
