Gravitation 01 | Universal Law of Gravitation | Class 9 | NCERT | Sprint 

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Newtons 4th law of motion :- A book remains in the state of rest and covered with dust until and unless internal and external exams appeared and then the speed of turning pages is directly proportional to the syllabus covered and the tension in the mind remains constant

Challenger questions: 1) Force will be doubled 2) If distance is doubled, force = F/4 If distance is tripled, force = F/9 3) Force will be 4 times the initial force Amazing lecture!❤

air also has gravity as particles present in air have mass and every object which has its own mass has gravity too👍

According to Newton's second law of motion, the force acting on an object is equal to its mass multiplied by its acceleration (F=ma). Therefore, if the mass of one object is double, the force between the two objects will also double.

Answer of challenger: a)F gets doubled when mass of one object is doubled. b)F becomes 1/4 of previous force when doubled. F becomes 1/9 of previous force when tripled. c)F becomes 4 times of previous force when masses of both bodies are doubled. LOVED THE SESSION!

Sir's pen is the best example of every chapter 😂

challenger questions:- 1.ans= The force between two objects is also doubled, if one of it doubled. 2.ans= If the distance between two objects doubled and tripled, so the force between two objects is decreases. 3.ans= if the masses between two objects are doubled so the force also increases. Great Lecture!!!!

Kon kon mere sath h ki agar us time Newton ke sir per apple nhi girta to aaj ye gravity nhi pdhni padti please vote for this 😂😂😂😂😂😂😢😢😢😅😅😅😅😅😂😂😂😂😂😂

I like the Teaching as You explain in Hindi...Students know English Very Well but still we catch Concept more Readily While Learning In Hindi...That's Why I like This Foundation more Than Bhedantu and Gunacademy...

This was my first youtube lecture of physics wallah foundation and I love it. Thank you sir for making this amazing video and make us understand this concept.

Sir I want you as my teacher in our school for physics

Homework questions - Q.1) force of attraction becomes double of the previous force. Q.2) force of attraction becomes 1/4th of the previous force(when distance is doubled) and force of attraction becomes 1/9th of the previous force(when distance is tripled). Q.3) force of attraction becomes 4 times of the previous force. Thank you sir for this wonderful session😊 Love you sir ❤

Sir Hume school me samjaya nahi, sirf ratta marvaya jata hai . Mam ko verbally Hindi me answer do to bolti hai English mein chahiye .sir pehle mujhe physics se nafrat thi lekin jab se aap padhate ho tab se physics mujhe pasand aane lagi Sir physics wallah ko apni ek school khol leni chahiye jaha pe bacho ko robot jaisa nahi insano jaisa treat Kiya jaye

Very Nice Explanation Sir, pls bring the deleted part also of this chapter

Challanger Question Ans. 1) Force will be twice 2)Force will be (i)1/4 of previous value...(ii) 1/9 of previous value.. 3)Force will be 4 times..... Thank you sir for great explaination😊😊

Any one noticed that _kar bhala to ho bhala _Newtown 🥉 law😂😂🎉

Ek apple 🍎🍎 ne zindgi barbaad kr di 😭😭😭😭🥺

Challanger question 1:- F=G.M1.M2/r².....(1) F=G.2M.M2/r².......(2) By dividing eqn 2 by 1 F¹/F=G.2M.M2/r²/G.M1.M2/r² F¹=2F. Answer

Challenger question's answer : 1. It will be twice. 2.1/4 of the previous in double and 1/9in triple . 3. 4 times more.

*Challenger Questions -:* Q. What happens to the force between two objects, if 1) the mass of one object is doubled ? *Sol-:* F = G×M1×M2/r².....(1) F⁰= G×M1× 2M2/r².......(2) Dividing eqⁿ 2 by 1 . Then, F⁰/F = G×M1×2M2/r² ÷ G×M1×M2/r² F⁰/F = 2/1 F⁰= 2F The force will be twice if the mass of one object will doubled. 2) (I) the distance between the object is doubled. *Sol-:* F= G×MI×M2/r².......(1) F⁰= G×M1×M2/4r².......(2) Dividing eqⁿ 2 by 1.Then, F⁰/F = G×M1×M2/4r² ÷ G×M1×M2/r² F⁰/F = 1/4 F⁰ = F/4 The first become one fourth if it's distance doubled. (II) the distance between the object is tripled. *Sol-:* F=G×M1×M2/r².....(1) F⁰=G×M1×M2/9r²........(2) Dividing eqⁿ (2) by (1).Then, F⁰/F = G×M1×M2/9r² ÷ G×M1×M2/r² F⁰/F = 1/9 F⁰= F/9 The force will be one-ninth if the distance will tripled. 3) the masses of both objects are doubled? *Sol-:* F = G×M1×M2/r².........(1) F⁰= G×2×M1×2×M2/r²......(2) Dividing eqⁿ (2) by (1).Then, F⁰/F = G×2×M1×2×M2/r2 ÷ G×M1×M2/r² F⁰/F = 4/1 F⁰ = 4F The force will be 4 times if the mass of both two objects are doubled. Hope ! This is correct 🥰🥰🥰🥰.

Thanks to Alakh sir for choosing the great teachers for us.

Sir session bahot accha tha.

Kaun kaun Saal bhr na padhker exam se ake din phele mobile se padhker pure chapter ko tyaar kerte hii... 😂😂😂

The hallo bachhoooooooooo is so good 0:01😂😂😅

Best explanation by best teacher !!💐💐

Challengers question 1) 2 times 2) 1/4 times and 1/9 times 3) 4 times

Always try to give extra information..... Thanku so much sir🙏🙏🙏

(i) F'= 2F (ii)If distance are doubled F'=1/4F. If distance are tripled F'=1/9rF (iii)F'=4F Answers of the homework questions.Thanks sir for the best explanation.My all doubts are clear in this video.🙏🙏🙏🙏🙏

8:35 - Yes, air will also have gravity because it has mass .

Challenger question 1:- force become twice 2:- 1/4 of the previous and 1/9 of the previous 3:- it becomes 4 times

Sir you teaches very nice 👍👍👍👍and thanks alot for the video🎥🥰🥰🥰 sir you are the best👍💯👍💯

8:46 Yes sir Air have Gravity and Gravitational force both because Air is made up of fine particles and all particles have some mass.

3:06 newton was sitting in his home and watched the tree of apple and a apple fall from tree. Newton thought that why this apple fall only downside, why it's not going upside or in any other direction. Then he discovered the *GRAVITY* . This was written in his *DOCUMENTARY* .

44:02 # Challenges question (I) The force will become doubled (2) A) when doubled force will become 4 times (2)B) when tripled force will become 9 times (3) The force will become 4 times Thank 🙏🙏you sir

Op sir you are really a good teacher in the whole team of sprint batch. Your teaching style like gravity which attracts me alot all time. THANK YOU SIR FOR PUTTING YOUR VALUABLE EFFORTS AND TIME.😊 THANK YOU ALAKH SIR 😊

36:11 , when 6.4 and 6.7 were canceled, all that's left is 60/6.4, which comes out to be 9.3, not 9.8, so that cancellation can't be done in the exam and the whole tedious calculation is required.

Your teaching is so good as compare to other teachers ❤️

Thankyou so much sir this video helped me so much 🙏best teacher I have ever seen🙏🙏thankyou for your teaching sir 🙏🙏🙏I appreciate your teaching 🙏

Challenger questions 44:03 Q1 I) Force will become 2 times greater than previous Force II) Forced will become F/4 and F/9 times III) force will become 4 times greater

Becoz of one apple 🍎 we are studying a huge tricky chapter

37:15 funniest motion 😂😂 Edit-Thanks for 1k like❤️❤️😘😘

Apple did not fall on Newton's head it was just observed by him falling Rakshak Sir Op 🔥🔥🔥🔥🔥

8:45 Yes sir air me bhi gravity h

Challenger questions: 1) Force will be doubled 2) If distance is doubled, force = F/4 If distance is tripled, force = F/9 3) Force will be 4 times the previous force. Amazing lecture!

Challenger Answers :- 1. New force is 2 times the older one. 2. ☆ New force is 1/4th the older one. ☆New force is 1/9th the older one. 3. The new force is 4 times the older one. Adbhut hai Sir aap.

Challenger question: 1. Let, Mass of 1 object be doubled=2M New force =G ×2Mm/d² =2×old force If the mass of one object is double the foce is also doubled. 2.If the distance is doubled, distance=2d Then, F=GMm/(2d)² =GMm/4r² =1/4×old force When the distance is doubled the force becomes 1/4 times of the old. 3. if the distance is tripled, distance =3d Then, F=GMm/(3d)² =GMm/9d² =1/9 ×old force When the distance is tripled the force becomes 1/9 times of old force.

Challenge question 1. If the mass of the object is doubled then the ans is F'=2xF 2. The distance when doubled then the ans is F'=1/4xF The distance when tripled then the ans is F'=1/9xF 3. If the masses of both the object increases the ans is F'=4xF

One of the best teacher of physics I have ever got❤️❤️❤️

Thanku so much sir.. You have great teaching style..🤗🙂🙂 I was dull in physics but because of you now I love physics and I have decided to take PCM after 10th..🤠🤠

Sir physics wallah ko apni ek school khol leni chahiye jaha pe bacho ko robot jaisa nahi ,insano jaisa treat Kiya jaye, ratta nahi samjhaya jaye Please sir alakh sir ko schools kholne ka idea zaroor dijiye Aur pune mein khaskar kholna near Hadapsar

Ek apple ke vajah se itna kuch phad na pad Raha hai agar apple 🍎 Mila hi tha toh kha leta kyu itne chuchle kiye 😂

Sir after seeing your video physics became my favorite subject 😊😊. THANK YOU SO MUCH

Question 1)- a)- the force is doubled. b)- force becomes 1/4 when radius between the object is doubled and becomes 1/9 when tripled. c)- the force is quadrupled.

Challenger answer 1: if force was F previously it becomes 2F. 2: force will be F/4 and F/9. 3: force will be 4F

What if Netwon sit under a coconut tree instead of a apple tree then the width of all science book would be like the width of economic book of class 9😂😂😅😂😂😅❤

11:45 1)moon revolve because of earth 2)Eart because of sun 3)Sun (soler system) because of supermassive black hole in center of gallexy 4)and gallexy because of center of the mass of gallexy cluster

Sir aapki Physics, biology aur geography bahut achhi hai

Who all loved his t shirt.. Kar bhala to ho bhala - Newton's third law 😂😂😆😅😅

sir not knowing answer in the air, gravitation force is there or not ? kindly tell me the answer

1.i) 2times of the previous force ii) doubled - 1/4 of previous force Tripled - 1/9 of previous force iii) 4times of previous force

3:06 sir mujhe to lagta hai nhi gira hoga ... Bas Newton ne diya hoga gravity ka ... Kyuki agar sach me girta to vo gravity ke bare me nhi sochta seb uthata khata aur ghar ja ke so jata ....😂

Yes sir ,Gravity is present in air also. That's why in the lower height pressure is higher and as we go higher the air pressure goes on decrease

Challenger question answers 1) If one of the masses is doubled then the force will double. 2) If the distance is doubled the the force will become half and if the distance is tripled then the force will be one-third. 3) If the masses are doubled(both the masses) then the force will be quadrupled.

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One more question How can the heart be strong enough to pump blood up your legs against gravity?

Yes sir air also have gravitation even an all the partical has the gravitational force between them and sir that's why radon is heaviest gas so it is at the lowest level of the ground and hydrogen is the lightest so it is at the top.

Sir your teaching method is very nice ☺️ thanks 👍👌🥰 sir 🎉

Challenger Questions:- (1) Fn=2F (2)(i) Fn =F/4 (ii) Fn = F/9 (3) Fn =4F

Q1 I) Force will become 2 times greater than previous Force II) Forced will become F/4 and F/9 times III) force will become 4 times greater

Even paid clases won't teach us like this......❤️ Thnku sir 😊

Thank you soo much Before I got 2/8 in my first exam Now I got 7/8 in my second exam Thank you soooo much !!

Answer of challenger questions. 1. F' = 2F. 2. F'= 1/4 F. F' = 1/9 F. 3. F' = 4F.

Yes sir , Air is applying force on us which is opposite to the gravitational force.

The moment when sir gives us extra knowledge which i love to have and then says kher chodo bade level ki bate hai and then leave that topic which i was actually able to learn pisses me off sir dont underestimate us

the mass is 2 time bigger than previous mass and when the distance is double then the distance is 1/2 and when the distance is tripled than mass is 1/3 and its four times bigger the previous mass....

2. If the distance between them is double then the force becomes 1/4 of the previous force . And if the distance between them is triple then the force becomes 1/9 of the previous force.

Mtlb phone mai sabse zada gravitational force hai 😂

Challenger questions answer---- 1.a) force will be double from actual force. b)in 1st case force will be 1/4 of actual force and in 2nd case force will be 1/9 of actual force c)force will be 4 times larger than actual force. Thanking you

I like the teacher as you explain in hindi ...... study know English very well but still we catch concept more readily while learning in hindi ... that's why l like This foundation more than Bhedan ❤❤❤❤❤❤😮😮😮

44:00 (1) the force becomes 2 times when the mass of one object is doubled (2)the force becomes one-forth times when the distance between doubled and the force becomes one - ninth times when distance between object is tripled. (3) the force becomes 4 times when the mass of both object is doubled. 😊

Best teaching ever I had seen ; before some months when I hadn't found this channel I was very weak in physics but now I had got full marks in physics due to PHYSICS WALLAH platform ...A very special thanks to ALAKH SIR and PHYSICS WALLAH TEAM •••.

9:31 Best part ❤️

1 ka force double hoga 2 ka double distance me force double hoga aur tripled distance me tripled hoga 3 ka force dono same rahega

sir your teaching is so good but sometimes we watch your videos to learn how to simplify bigger digits(the last part of every question). it would be so helpful if you will simplify it too.

You are great sir ur teaching style attract me always👑👑 , sir we need again a new batch for class 9. Like a sprint batch ... .. 😊🙌🙏🙏

8:37 yes sir Air mein bhi gravity because air mein small particles hote h unme bhi Mass hota h issiliye Air mein bhi gravity hoti h 😊😊

Thanks for better understanding 6:55 Best teacher of world Of physics

Challenger question answers:- 1) Force will become 2 times of initial force. 2) when the distance b/w two objects is doubled than force will become 1/4th of its initial value and when it is tripled it will become 1/9th of its initial value. 3) force will become 4times when masses of both the objects are doubled. & Air also has gravity because it has mass.

Sir I have a request to all physics wallah platform not to remove any topics from any chapter because not in every school not that topic is removed and children will read these lectures after some years so please don't remove it or if you remove it also then when you get free time then upload it..🙏🙏

since air contains some mass/some volume so we can consider that air also HAVE some gravitational force in it , but since its mass is really light and small , its gravitational force wont to be powerful enough, thAnks for the video sir

😊sir, I really like this video thank you

Sir just because of you physics is my favourite subject now..😊😊

Grt lecture sir... 👍🏻👍🏻 THANK U SIR

Thanks a lot sir....💜💜 Seems like.. would never get a teacher like u!! U r fantastic sir!! Keep going..😊😊

i=the force will increase. ii=the force will be decrease by 5 times. iii=the force will increse by two times. 44:02

Sir aap konse state/city se padha rhe ho

Your are best teacher and I love yr teacher style👍

I think this lesson is so hard, but I see your vidio my mind is changed now, I am thik this chapter is so interesting. 📚🤗

Hii sir..... Your lecture is so much good