7️⃣ FORCE by https://padlet.com/amalabhass303/g3oucxo0cc66bz14 en-us 2020-12-22 18:52:44 UTC 2024-03-30 06:18:01 UTC hello@padlet.com amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038624312 DIGITAL TEXT ON THE CHAPTER " FORCE "
----------------------------
(8th Standard Physics )

Submitted by,
AMALABHAS S
Roll no : 2
Physical Science 
KUCTE, Kayamkulam
2019 - 2021



]]> 2020-12-22 18:56:48 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038624312 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038626114 Observe the pictures given below

]]> 2020-12-22 18:57:50 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038626114 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038627805 What do you observe in these two pictures? 🤔]]> 2020-12-22 18:58:48 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038627805 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038635525 In fig. (a), a man is pulling a hand trolley.
In fig. (b), a man is pushing a car. ]]> 2020-12-22 19:03:15 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038635525 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038647744 Then, can you identify whether the following are push or pull? 

]]> 2020-12-22 19:10:39 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038647744 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038650021 From all these things what did you learn?

When an object is pushed or pulled, a force is being applied on it. ]]> 2020-12-22 19:12:13 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038650021 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038652450 From all the examples given above, can you state what force is? ]]> 2020-12-22 19:13:52 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038652450 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038655363 " Force is that which changes or tends to change the shape, size, volume, state of rest or state of motion of a body.  
The unit of force is newton. It is indicated by the letter 'N' "]]> 2020-12-22 19:15:49 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038655363 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038665066 More information about the origin of the unit of force "newton" and the biography of Sir, Isaac Newton...👇

https://www.curriculumvisions.com/search/N/newton/newton.html]]> 2020-12-22 19:22:05 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038665066 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038675297 CONTACT AND NON CONTACT FORCE

Observe the pictures

]]> 2020-12-22 19:27:44 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038675297 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038677415 What is the difference that you can observe in each of these pictures?🤔]]> 2020-12-22 19:29:11 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038677415 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038687885 The figures (a), (b) and (d) shows situations where force is applying by the contact between objects.

The figures (c), (e) and (f) shows situations where force is applying without the contact between objects. ]]> 2020-12-22 19:36:02 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038687885 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038693006 The can you state what are contact and non contact forces? ]]> 2020-12-22 19:39:23 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038693006 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038699839 "The force applied by the contact between objects is called contact force."

"The force applied on an object without contact on it is called non contact force." ]]> 2020-12-22 19:44:22 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038699839 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038708487 FRICTIONAL FORCE

Observe the video well
]]> 2020-12-22 19:50:21 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038708487 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038709453 What you have learned? ]]> 2020-12-22 19:51:05 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038709453 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038712777 "When a body moves or tends to move on the surface of another body, a force is experienced parallel to the surface which opposes the relative motion between them. This is known as friction."]]> 2020-12-22 19:53:34 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1038712777 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039605618 DIFFERENT TYPES OF FRICTION

Observe the following picture in which two children are trying to move a log.

]]> 2020-12-23 09:22:07 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039605618 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039608204 2020-12-23 09:24:59 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039608204 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039613963 Which of these methods is easy in moving objects - by dragging or by rolling? 🤔]]> 2020-12-23 09:31:30 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039613963 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039624545 Let's watch a video related to this.
Video link...👇
https://youtu.be/eNRqHWPn1iQ]]> 2020-12-23 09:42:49 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039624545 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039626496 So what can we conclude? 

]]> 2020-12-23 09:45:04 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039626496 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039629876 "When a body rolls over the surface of another body, the force of friction which originates is rolling friction." 

"When a body slides on the surface of another body, the force of friction which originates is sliding friction."

Rolling friction is less than 
sliding friction.]]> 2020-12-23 09:49:05 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039629876 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039715281 For further study, watch the following video
Video link... 👇
https://youtu.be/zF0m8lZra-E]]> 2020-12-23 11:28:54 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039715281 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039721883 THRUST AND PRESSURE

Observe the following cartoon. 

]]> 2020-12-23 11:37:11 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039721883 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039722793 Why the boy is saying so? Have you ever think about this? ]]> 2020-12-23 11:38:18 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039722793 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039722989 Observe the following video]]> 2020-12-23 11:38:37 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039722989 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039723170 What we learned? ]]> 2020-12-23 11:38:54 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039723170 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039726096 "The total normal force experienced by a surface is thrust." 
"Thrust per unit area is pressure." 

Pressure = Thrust / Area

From this equation we can conclude that the unit of pressure is N/m^2. This is known as pascal. ]]> 2020-12-23 11:41:56 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039726096 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039729128 LIQUID PRESSURE

Fix identical balloons A, B, C on a PVC pipe as shown in the figure given below. Observe the expansion of balloons on filling water in the pipe. 

]]> 2020-12-23 11:46:00 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039729128 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039730779 2020-12-23 11:48:28 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039730779 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039732250
  • Which balloon has expanded more? 
  • What may be reason? 
  • How can the expansion of balloon be related to the depth of the level of liquid in the pipe? 

    • ]]>     2020-12-23 11:50:14 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039732250     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039732903 By answering the above questions, what idea you got finally? 

    The pressure exerted by a liquid column increases with increase in height. 
    "The thrust acting per unit area by a liquid is liquid pressure. "
    Liquids exert force on all sides of the container in which they are taken.     ]]>     2020-12-23 11:51:07 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039732903     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039736688 Now observe the following video
    Video link👇
    https://youtu.be/Cvp6mLWbgaM]]>     2020-12-23 11:56:08 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039736688     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039737097 What do you understood from the video? ]]> 2020-12-23 11:56:46 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039737097 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039742022 If the height of the liquid column is 'h', density of liquid 'd' and acceleration due to gravity 'g', then liquid pressure is P = hdg]]> 2020-12-23 12:04:02 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039742022 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039743303 ATMOSPHERIC PRESSURE

    Observe the following video
    Video link... 👇
    https://youtu.be/KndNN28OcEI]]>     2020-12-23 12:05:43 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039743303     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039744030 So what can we sum up? ]]> 2020-12-23 12:06:36 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039744030 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039747406 An envelope of air surrounds the earth. This is the earth's atmosphere. The density of atmospheric air near the surface of the earth is greater and it decreases as we go up. 
    The weight of the air column over unit area of the earth's surface is atmospheric pressure.     ]]>     2020-12-23 12:11:01 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039747406     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039753477 FOR DETAILED STUDY

    https://en.m.wikipedia.org/wiki/Atmospheric_pressure]]>     2020-12-23 12:18:38 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039753477     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039831740 SIGNIFICANT LEARNING OUTCOMES

    The learner can
    • explain what force is and what the results of applying a force are.
    • identify different types of forces and classify them into contact and non contact forces.
    • explain friction and identify its advantages and disadvantages and use it in daily life situations.
    • explain thrust and pressure. 
    • use the relation between area and pressure in appropriate situations.
    • explain liquid pressure and engage in experiments that show the relation between pressure and height.
    • explain what atmospheric pressure is and use it appropriately in daily life situations.

    ]]>     2020-12-23 13:32:46 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039831740     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039842578 ANSWER THE FOLLOWING QUESTIONS

    1) Classify the following situations into contact and non contact forces. 
    • Applying break in a bicycle.
    • A mango falling from a mango tree. 
    • The earth revolving around the sun. 
    • The speed of a ball rolling on ground is reduced. 
    ]]>     2020-12-23 13:39:56 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039842578     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039848298 2) State reason. 
    • We are able to walk on the ground without slipping. 
    • It is easy to cut vegetables using a sharp knife. 
    • The number of tyres is more for goods vehicles. 
    • The moving parts of machines experience wear and tear.

    ]]>     2020-12-23 13:42:54 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039848298     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039864309 3) Fill in the blank. 
    • FORCE : newton
    • _______ : pascal
    ]]>     2020-12-23 13:53:29 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039864309     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039872026 4) List the situations in daily life where atmospheric pressure is used.
    • drinking juice using a straw.
    •     
    •   
    ]]>     2020-12-23 13:58:28 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1039872026     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040214519 5) List the factors influencing liquid pressure. ]]> 2020-12-23 17:34:44 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040214519 amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040229545 6 ) Match the following. 

    ]]>     2020-12-23 17:45:42 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040229545     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040230589 SOLVED QUESTIONS

    https://www.hsslive.guru/kerala-syllabus-8th-standard-basic-science-solutions-chapter-10/]]>     2020-12-23 17:46:38 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040230589     amalabhass303 https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040308859 Video link for contact and non contact forces...👇
    https://youtu.be/x1BR72OzQmE]]>     2020-12-23 18:52:46 UTC https://padlet.com/amalabhass303/g3oucxo0cc66bz14/wish/1040308859