S9. Motion and Types of Motion | Physics | Class 6

Q1. Identify the types of motion.

1. Movement of the earth around the sun : ………. . 

Answer: periodic, circular

2. Movement of a ceiling fan : ……….

Answer: circular

3. A meteor falling from the sky :………. .

Answer: linear

4. A rocket launched from the ground : ……….

Answer: linear

5. A fish swimming in water : ……….

Answer: random

6. The plucked string of a sitar : …….

Answer: oscillatory motion

Q2. Fill in the blanks.

1. If a ball is released from the terrace of a building, it comes down in ……….. motion. On the other hand, it reaches the ground in ……….. motion if it is thrown with force away from the terrace in a direction parallel to the terrace.

Answer: uniform linear, non-uniform linear

2. The motion of an aeroplane on the runway before take-off is………. .

Answer: linear

3. The kite looking for its prey ies with ………. motion in the sky.

Answer: circular

4. Children sitting in a rotating giant wheel have ……….. motion, while those sitting in a merry-go-round have a ……….. motion.

Answer: uniform-circular, non-uniform circular

Q3. How are we different ?

1. Oscillatory motion and linear motion.

Oscillatory motion	Linear motion
1. In oscillatory motion the motion of the body is to and fro (or swings back and forth)	In linear motion the motion of the body is in a straight line
2. Example:  motion of a swing, motion of a pendulum of a clock	Example: motion of train, motion of marching soldiers

2. Linear motion and random motion.

Linear motion	Random motion
1. In linear motion the motion of the body is in a straight line	In random motion the motion of the body continuously changes its speed and direction.
2. Example: motion of train, motion of marching soldiers	Example: motion of bird, motion of mosquito

3. Random motion and oscillatory motion.

Random motion	Oscillatory motion
1. In random motion the motion of the body continuously changes its speed and direction.	It is a motion of a body that is swinging back and forth.
2. Example: motion of bird, motion of mosquito	Example: wings of bird, pendulum of clock

Q4. Explain in your own words, giving one example each.

1. Linear motion:

The motion of a body that is in a straight line or in the same direction is called linear motion. Example: A train or a moving vehicle on a road.

2. Oscillatory motion:

The motion of a body that is moving back and forth or to and fro is called oscillatory motion. Example: A swing, or a pendulum of a clock.

3. Circular motion:

The motion of a body that is moving along a circular path is called circular motion. Example: motion of blades of fan, merry-go-round.

4. Random motion:

1. The motion of a body that is changing its direction and speed continually is called random motion. Example: motion of bird, motion of mosquito

5. Periodic motion:

The motion of a body that is completes one round or one oscillation in a fixed period of time is called periodic motion. Example, the minute hand of a , merry-go-round.

Q5. Answer the following questions in your own words.

(a) Which types of motion are seen in birds flying in the sky ?

ANSWER: Birds flying in sky show random motion. Wings of flying bird shows oscillatory motion.

(b) Write in detail about your experience of various types of motion while riding a bicycle on a road.

ANSWER: While riding a bicycle we see following motions of different parts of bicycle:

• a) The wheels show circular motion
• b) Cycle shows linear motion
• c) If the speed is constant it shows periodic motion
• d) The handle bar shows random motion

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