# Motion & Types of Motion Std 6 Ch 9 question & answers

## Exercise

1. Identify the types of motion.

(a) Movement of the earth around the sun: Circular Periodic Motion

(b) Movement of a ceiling fan: Circular Motion

(c) A meteor falling from the sky: Non-uniform linear Motion

(d) A rocket launched from the ground: Non-uniform linear Motion

(e) A fish swimming in water: Random Motion

(f) The plucked string of a sitar: Oscillatory Motion

2. Fill in the blanks.

(a) If a ball is released from the terrace of a building, it comes down in non-uniform linear motion. On the other hand, it reaches the ground in non-uniform linear motion if it is thrown with force away from the terrace in a direction parallel to the terrace.

(b) The motion of an aeroplane on the runway before take-off is non-uniform linear motion.

(c) The kite looking for its prey flies with random motion in the sky.

(d) Children sitting in a rotating giant wheel have circular motion, while those sitting in a merry-go-round have a circular motion.

(Linear, non-linear, circular, uniform linear, non-uniform linear, uniform circular, non-uniform circular, random)

3. How are we different?

(a) Oscillatory motion and linear motion.

 Oscillatory motion Linear motion The motion of a body that is swinging back and forth, is called oscillatory motion. The motion of an object moving in a straight line or in the same direction is called linear Motion. For example: Movement of the pendulum of a clock For example: Vehicles moving on a straight road

(b) Linear motion and random motion.

 Linear motion Random motion The motion of an object moving in a straight line or in the same direction is called linear Motion. The motion that changes its direction and speed continually is called random motion. For example: Vehicles moving on a straight road For example: Butterflies flying in a garden.

(c) Random motion and oscillatory motion.

 Random motion Oscillatory motion The motion that changes its direction and speed continually is called random motion. The type of motion in which the object moves to and fro repeatedly about a mean or a fixed position is known as oscillatory motion. For example: Butterflies flying in a garden. For example: Movement of the pendulum of a clock

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

(a) Linear motion: The motion of an object moving in a straight line or in the same direction is called linear Motion. For example: Vehicles moving on a straight road.

(b) Oscillatory motion: The motion of a body that is swinging back and forth, is called oscillatory motion. For example the flapping of the wings of the birds.

(c) Circular motion: The motion of an object along a circular path is called circular motion. For example rotating giant wheel.

(d) Random motion: The motion that changes its direction and speed continually is called random motion. For example children playing in the park.

(e) Periodic motion: The motion of an object which passes through a certain point again and again after a fixed period is called periodic motion. For example rising and setting of the sun

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

Ans. Birds flying in the sky show oscillatory motion.

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

Ans. While riding a bicycle I experience the following motion:

Uniform linear motion

Non uniform linear motion

Circular motion

6. Complete the puzzle using words for types of motion:

(1) a spring is stretched and one end is released

(2) a minute hand

(3) a see saw

(4-5) children in a march past

(6) a stone rolling down a hillside.

 o s c i l l a t o r y i p e r i o d i c c u n i f o r m l l i n e a r r a n d o m

#### Activity :

Make a list of various moving objects in the environment, and discuss the types of motion seen in them.

### Extra Question:

1. What is motion?

Ans. The continuous displacement of an object is called motion.

2. What is Linear motion?

Ans. The motion of an object moving in a straight line or in the same direction is called linear Motion.

3. What Uniform linear motion?

Ans. When the distance traversed by an object along a straight line in unit time is continuously the same, the motion is called uniform linear motion.

4. What is Non-uniform linear motion?

Ans. When the distance traversed by an object along a straight line in unit time keeps on changing, the motion is called non-uniform linear motion.

5. What is oscillatory motion?

Ans. The motion of a body that is swinging back and forth, is called oscillatory motion.

6. What is circulatory motion?

Ans. The motion of an object along a circular path is called circular motion.

7. What is periodic motion?

Ans. The motion of an object which passes through a certain point again and again after a fixed period is called periodic motion.

8.  What is random motion?

Ans. The motion that changes its direction and speed continually is called random motion.

9. What is speed?

Ans. The distance traversed by an object in unit time is called the speed of that object.

10. What is displacement?

Ans. Change of place of an object is called displacement.

11. What kind of movement does a swing in a park show?

Ans. A swing in the park shows oscillatory motion.

12.  Give examples of oscillatory motion.

Ans. Examples of oscillatory motion are the movement of the pendulum of a clock, the wings of a bird, the needle of a sewing machine, the vibrating diaphragm of a tabla or drum.

13. Give examples of circular motion.

Ans. Examples of circular motion are hands of clock, a fan, a giant wheel, a merry-go-round, etc.

14. Which types of motion are seen when a girl rides a bicycle as shown here?

Ans. This picture shows oscillatory motion and periodic motion.

15. A bus covers the distance of about two hundred kilometres from Solapur to Pune in five hours. How much distance does the bus cover in one hour?

∴ The bus travels 80 km in one hour.

Fill in the blanks:

1. Moving objects are said to be objects in motion.

2. Change of place of an object is called displacement.

3. An object in motion continuously undergoes displacement.

4. The continuous displacement of an object is called motion.

5. The motion of an object in a straight line or in the same direction is called linear motion.

6. An object in linear motion shows displacement along a straight line.

7. The motion of soldiers in a parade is uniform linear motion.

8. The motion of the girl coming down the slide non-uniform linear motion.

9. When the distance traversed by an object along a straight line in unit time is continuously the same, the motion is called uniform linear motion.

10. When the distance traversed by an object along a straight line in unit time keeps on changing, the motion is called non-uniform linear motion.

11. The motion of a body that is oscillating, i.e., swinging back and forth, is called oscillatory motion.

12. The movement of a swing is called oscillatory motion.

13. The movement of the pendulum of a clock, the wings of a bird, the needle of a sewing machine, the vibrating diaphragm of a tabla or drum are also examples of oscillatory motion.

14. The motion of an object along a circular path is called circular motion.

15. The motion of an object which passes through a certain point again and again after a fixed period is called periodic motion.

16. The hands of a clock, a fan, a giant wheel, and a merry-go-round are examples of circular, oscillatory and periodic motion.

17. The motion that changes its direction and speed continually is called random motion.

18. The motion of a butterfly that constantly flits from one flower to another is called random motion.

19. The motion of the players in a game of football, a crawling baby or a wandering animal are examples of random motion.

20. The distance traversed by an object in unit time is called the speed of that object.