Explore topic-wise InterviewSolutions in .

1. The direction of motion of the objects changes alternatively along the same path about a fixed point. Hence the direction of motion of the object not constant. 

2. Yes, they are moving in the same path again and again.

1. The strings of veena and needle of sewing machine are moving in ‘to and fro’ motion or back and forth motion. 

2. The direction of motion of the objects changes alternatively along the same path about a fixed point. 

3. Hence, we can say that they are in oscillatory motion or vibratory motion.

1. The relation between distance and time can be understand in terms of speed. 

2. The distance travelled by an object in a unit time is called as speed. 

3. If an object takes less time to cover more distance, the speed will be more. 

4. If an object takes more time to cover less distance, the speed will be less.

Rockets are devices that produce force or push needed to move an object forward.

Motion: A meaningful or expressive change in the position of the body or a part of the body a gesture.

The motion of all particles of a moving body follows a circular path with respect to a fixed centre or axis of rotation.

1. “If a body covers equal distances in equal intervals of time, it is said to be in uniform motion.” “If a body covers unequal distances in equal intervals of time, it is said to be in nonuniform motion.” 

2. Observe the movement of hands in a wall clock and the movement of a butterfly in a garden. 

3. Measure the angle between two successive positions of the minute hand in a wall clock. 

4. You can observe that the change in its position is same for every minute. 

5. But in the case of the butterfly, the change in its position is not constant while it is . flying from one flower to another in the garden. 

6. We understand that the minutes hand in wall clock covers equal distances in equal intervals of time and the butterfly covers unequal distances in equal intervals of time. 

7. Hence we can say that the minutes hand in a wall clock has uniform motion and the butterfly has non-uniform motion.

Examples:

1. Coconut falling from a tree. 

2. Movement of lift. 

3. Car travelling on a straight road. 

4. Movement of water from the tap.

Correct option is C) Movement of a pendulum

We classify the motion of bodies as 

• Translatory motion 
• Rotatory motion 
• Oscillatory motion.

Uniform and non-uniform motion:

1. A body is said to be in motion if its position keeps on changing with time (with respect to the observer). 

2. But in our daily life we experience certain motions in which, the change in position of objects remains the same for a time interval, in some other motions, the change in position of the object will not be the same for a given time interval. 

3. Uniform motion (Definition): If a body covers equal distances in equal intervals of time it is said to be in uniform motion. 

4. Non – Uniform motion (Definition): If a body covers unequal distances in equal intervals of time, it is said to be in non – uniform motion.

1. Motion is a common experience in our life. We observe birds flying in air, buses, autos, cars, bullock carts, moving on roads, trains on railway tracks and many other objects around us in motion. 

2. Apart from observing motions of objects around us, we ourselves experience motion while we are walking, running, playing, riding a bicycle etc. 

3. Similarly, we observe many objects like trees, buildings, display boards, electric poles etc., at rest while we walk to school.

The ‘to and fro’ motion of an object about a fixed point that always following the same path is called oscillatory or vibratory motion. 

Ex: 

motions in swing, strings of veena, needle of sewing machine etc.,

Correct option is D) Kite

1. Uniform motion : If a body covers equal distances in equal intervals of time, it is said to be in uniform motion. 

2. Non – uniform motion : If a body covers unequal distances in equal intervals of time, it is said to be in non – uniform motion.

If a body covers unequal distances in equal intervals of time, it is said to be in non uniform motion.

If a body covers unequal distances in equal intervals of time, it is said to be in nonuniform motion.

1. We observe many objects in motion in our daily life. 

2. In some cases objects move slowly and in other cases they move fast. 

3. To know whether the motion is slow or fast Let us assume that you started to school on a bicycle and your friend started in a bus at the same time from a place. 

a) My friend reached the school first. Because he started in a bus and I started on a bicycle. 

b) Bus reaches the school fast. It means bus took less time to reach the school. Bicycle took more time to reach the school.

1. Yes. I agree with him. Because rockets move with the speed of 12 km per second. Its very high speed. 

2. The distance travelled by an object in a given interval of time can help us to decide whether it is faster or slower. 

3. The distance travelled by an object in a unit time is called as its Speed. 

4. Speed = Distance travelled / Time taken to travel. 

5. Units of speed is meter per second (m/s) or kilometre per hour (Km/h). 

6. 1 Km / h = 5/18 m/s 

7. The object moving with less speed is slow and more speed is fast. Thus we can decide whether the motion of a body is slow or fast using its speed. 

8. At a particular instant of time, we can find speed of a vehicle using speedometer.

If all points of a moving object move through the same distance in same direction, then the motion is said to be translatory motion. 

Ex: 

Coconut falling from a tree, movement of lift, car travelling on a straight road etc.

If a body covers unequal distances in equal intervals of time, it is said to be in non uniform motion.

Speedometer helps us to know the speed of a vehicle.

Yes, we need to know about distance covered, time taken by the body in motion, to decide whether the motion is slow or fast.

An object is said to be in motion, if it changes its position with respect to surrounding and an object is said to be in rest, if it doesn’t change its position with respect to surroundings.

The correct option is A) Translator motion.

The distance travelled by an object in a given interval of time can help us to decide whether it is faster or slower.

1. distance travelled 

2. Speed 

3. K. Sivan 

4. Rockets 

5. translatory 

6. rotatory 

7. motion 

8. rest 

9. Force 

10. distance 

11. centimeter 

12. metre 

13. displacement 

14. time. 

15. second 

16. 60 

17. decade 

18. Clocks /watches 

19. Stop clocks 

20. month

An object is said to be in motion if it changes its position with respect to its surroundings in a given time.

a) 

1. We observe that in case of the wall clock, Change in position of minute hand is same for every minute. 

2. How do we know this? 

3. Measuring the angle between two positions of the minute hand is the way.

b) 

1) But in the case of the butterfly, the change in its position is not constant while it is flying from one flower to another in the garden.

Stomata and lenticels help in the exchange of gases in plants.

Translatory motion.

The correct answer is Time.

Time to travel

The correct option is A) Movement of butterfly.

Answer is -------------

(a) both A and B. 

Correct option is D) Rotatory

(c) Time interval of 5 minutes can be measured by both A and B.

1. Plants respire like us. 

2. But it is difficult to observe this through experiments. 

3. Both plants and animals use oxygen during respiration.

Correct option is D) Oxygen

The correct answer is Distance.

1. In the above situations, the parts of the objects move in a curved path with respect to a fixed centre or a fixed axis.

2. They are in rotatory motion with circular path.

Correct option is B) Curvilinear motion

Correct option is D) Heart

Correct option is A) Trache

1. You may have heard of big hospitals keeping cylinders filled with oxygen. 

2. When a person has breathing problems he is given oxygen. 

3. An oxygen mask is fitted to the nose and mouth of the person and a rubber tube connects the mask to the oxygen cylinder. 

4. Sometimes a patient is given oxygen during an operation.

(a) The pain in her legs could be because of the accumulation of lactic acid in the muscles. During heavy
exercise or running, etc., the muscle cells respire anaerobically and produce lactic acid.
(b) The massage gave her relief because it improves the circulation of blood leading to increased supply of oxygen to the muscle cells which helps in complete breakdown of lactic acid into CO2 and water.