# Definition Of Motion

## Definition Of Motion

Change in position of an object with respect to time.

A moving object changes its position as the time passes/changes.
In general motion is described as the movement of object.
Objects which are moving will not be at a same position after certain interval of time.
When the object remains at same position after certain interval of time then the state of the object is known as "rest".
Examples of objects in rest and motion

 Objects at rest Objects in motion A building Moving airplane Table, Desk, Chair Second’s hand of the clock Person standing on the platform (waiting for train) Moving train� (reaching the station)

Change in position of an object with time is measured with the units of distance.� It describes the speed of an object.� (How fast or slow an object is moving.)
General types of motion: Circular motion, Periodic motion, rectilinear motion.

• Examples of different types of motion:
1. Translatory Motion: March-past of soldiers in a parade
Motion of a stone dropped from a building.
2. Circular Motion: Blades of an Electric fan (Switched on).
3. Periodic Motion: "Child on a swing"
"Motion of needle in a sewing machine".

•

#### Worked Example:

Sam participated in a sports event. In which he has to cover the circular ground for 3 times and he completes his first round in 5 minutes, the second round in 3 minutes and third round in two minutes. Which type of motion was covered by him? And in which round he moved very fast.

A. Periodic motion: 2nd round
B. Translatory motion: 1st round
C. Circular motion: 3rd round

#### Solution

Step 1: Sam covers a circular path in the sports event, hence he is in circular motion.
Step 2: In all the three cases he covers the same path.
Step 3: Hence the distance is same in all the three cases.
Step 4: First round was covered in 5 minutes, second round was covered in 3 minutes, third round was covered only in 2 minutes, hence the last round was covered with more speed as in short time he covered the complete path.
Step 5:

#### Worked Example

Which of the given example is in Periodic Motion?

A. Horse riding in a race
B. Simple pendulum of a wall clock
C. Motion of a giant wheel.

#### Solution

Step 1: Horse moves in a straight line motion during the race, hence it is in Translatory motion.
Step 2: Simple pendulum of a wall clock repeats the same path in equal interval of time, hence it is in periodic motion.
Step 3: Giant wheel moves in circular path, hence it is in circular motion.

Related terms: Speed | Velocity | Acceleration