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HW Questions Solutions Q3:-) Total momentum of two player =m1×u1 + m2×u2 =60(5)+55(−6) =300−(330) =−30 Kgms Total momentum of two collision =m1×v1+ m2×v2 =(m1+m2)v Conservation of momentum -30=(m1+m2)v V=115/−30 V=−0.26m/s Hence, player1 will be pushed by player2 Q4:-) [1 = rifle , 2= bullet] m1 = 4 Kg m2 = 50 g = 0.05 Kg u1=u2= 0 v1= ? v2= 35m/s 🟢Momenta of bullet & rifle (before Collison) = m1u1 + m2u2 = 4x0+0.05x0 = 0 🟢Momenta of bullet & rifle (After Collison) = m1v1+m2v2 = 4xv1 + 0.05x35 = 4v1 + 7/4 ❤️According to Law of Conservation of Momentum 🔴Momenta of bullet & rifle (before Collison) = Momenta of bullet & rifle (After Collison) => 0=4v1+7/4 => 4v1= -7/4 => v1 = -0.4375 m/s Hence Recoil Velocity of Rifle is 0.4375 m/s

At 37:15, the sum of masses was to be 1+5= 6kg

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Sir mai ap ka bhut bda fan hun❤️✌️ Jo v rakshak sir ka fan h Like kro😊

Q3. 32:40. :-l M1= 60kg U1= 5 m/s M2 = 55kg U2 = 6 m/s Player 1 from right to left ; player 2 from left to right M1U1 + M2U2 = M1V1 + M2V2 60(5) + 55(-6) = 60V1 + 55V2. {Common V1 and V2 is Vc ( because it will move in left direction as player two is having more initial velocity)} 300 + (-330) = Vc (60 + 55) -30 =. Vc (115) -30/115 = Vc -.26m/s = Vc from left to right Q4. 33:15:-) M1=4kg M2= 0.05kg U1=0 U2=0 V2=35m/s M1V1 +M2V2 =M1U1 + M2U2 4(V1) + (0.05(35)) = 0 4(V1) + (7/4) = 0 (16V1 + 7)/4 = 0 16V1 +7 = 0 * 4 16V1 = -7 V1 = -7/16 m /s The answer will be negative, because it's the rifle recoils backwards when the bullet is fired....

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33:00 Q-3-- ans = -0.260 m/s toward the direction of 1st player. (both final velocity were same because they 31:28 Q-4 --ans = 0.4375 are entangled)

At 37:15, the sum of masses was to be 1+5= 6kg.

Sir I had studied it by 2 teachers but I understand yours... because your teaching style of point to point makes study very easy... thanks sir👏🏻👏🏻

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School wali ma'am after watching this lecture be like :- Tho kya karun main job chodd dun ❗😂😂

Sir concept building q.5 mai - RHS side pe 10 = Vc( 5+1 ) 10 = Vc( 6 ) 10 = 6vc 10/6 = Vc So, Vc = 1.66 m/s

sir in concept building q5 the ans should be1.66m/s instead of 2m/s its not a big of a deal because the way u make us understand concepts is just impressive mistakes like these could be neglected and even the best teachers could make these mistakes great explanation sir thanks a lot:)

All doubts cleared.Thank u Rakshak sir❤❤

Sir can you please give a lecture to us based on combined numericals of all lectures 🥺 Sir Pyaare bacho ke liye itna sa kardo

I am really grateful to you Rakshak Sir. I had many doubts before watching your video. I was very sad. But after finding you my ideology for physics has been changed. Now I am feeling confident. Thank you so so much sir. I have no words to express my gratitude. I hope to join your class next year. Your name is appropriate for you. Thank you very much once again.🙏🙏 Shalini

31:41 ans. Velocity will be 0.26ms-¹ and movement is from mass2 to mass1

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Momentum physics ki jaan hai Newton ka third law uspar kurbaan hai 🤣

Thank you sir for such an amazing session 👍😍 really nice explanation

Q.3)-> The player of mass 55kg will move towards the player of mass 60kg with the common velocity of -0.26m/s

Sir I've completed half of the 9th and have studied from 10+ teacher but you are the best one by far.

Best teacher of physics of 9th standard...... Literally I got interest in physics after watching your video for the first time............. 🌈❤️

What a session!! Understood each and every part explained by a genius of Physics.........

Sir at 37:20 5+1 equals 6

Best physics teacher i have ever seen . Thanks a lot sir for your hardwork and dedication .

Bouyouncy and Archimedes principles and thrust and pressure

37:18The correct answer would be 1.67 m/s as m1 was added with m2

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Q3- m1=60kg,u1= 5m\s m2=55kg ,u2= -6m\s v1 and v2 is common. m1u1+m2u2=m1v1+ m2v2= -30=Vc(60+55) -30=115Vc Vc=-30\115 Vc=-0.26Ans

I am in class 11 but still watching these class for basic concepts clearing 🥺🥺

Thank you so much sir. Great explanation! All my doubts got cleared!..

In 37:10 the total mass is 6 kg not 5 kg

Sir ek doubt hai. When light is incident on the interface of glass- vaccume medium going from glass to vaccume the is dispersion happens. Plzzz answer me

The velocity=-0.26,from right to left the velocity=-0.43,in the opposite direction

Sir in question 1 we hadnt took one of the velocities as "-" due to difference in direction but in question 3 we are , since we are using the same formulae why are the applied rules different? should we put "-" in question 1 as well.

Q-3 Vć=-6/23 Direction= westward (negative axis)

Question no.3)- -0.26m/s (-) sign indicates that is opposite in direction means they move in left direction. Question no.4)- -0.43m/s it is negative because it moves direction opposite to that of bullet. Question no.2)- 4.65m/s. Hope it helps.

37:25 Sir If you don't mind Ek problem h 1+5= 6 hoga Aapne 5 likha And 2m/s aaya V 1.667m/s hoga 🙏

Really sir after watching your video my all doubt is clear your are next level physics teacher 🤩

Concept building Q-3--> Ans--> 60x5+55x-6=v(60+55).......as both got entangled 300-330=115v -30/115=v -0.26m/s=v they move towards the player who has p=330 as it is greater than the other

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31:07 Ans. 4.651m/s

37:16 In place of 5 it's 6 (5+1). Then 𝙫=1.66𝙢/𝙨. The total momentum just before and after the collision is 10 𝙆𝙜𝙢/𝙨

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Archemedies principle says - ME TOO

Sir there is a mistake in the question of "an object of mass 1 kg travelling with a velocity of 10m/s" In this question you forget to add 1 and 5 together and the common velocity come 10/5 means 2 m/s Which was wrong the real velocity is 1.6 m/s This is not your mistake, sir you are the best physics teacher i ever studied this can be a common mistake which is generally happens during calculations ❤️❤️ Love you PW ❤️❤️

Sir very nice class 🔥🔥🔥 Really enjoyed studying 🙏

A best way of teaching 🙏

My favourite master teacher...God bless you sir

This topic is deleted from ncert but it is very important that's why I see this video 🙂🙂🙂🙂

Question 5 answer is wring because 5+1=6 and then divide by 10 so answer is 1.6..m/s not 2❤❤

Bestest teacher and physics wallah group is superb. Thanku so much for clearing my doubts

Sir THANKS for This Lecture 😊😊♥♥👌👌👍👍

Answer of Q.4 was v1=-4.37m/s 😊

Sir your teaching is really amazing 👍

Towards left (the direction towards which yellow player is moving ) with the velocity of 0.26 m/s (only magnitude if direction included then , -0.26) I took the velocity common as you taught and the question is also suggesting that

Sir at 37:27 it would be 10/6

37:15 sir here you took Vc × 5,but the the sum of Vc(1+5) should result into Vc×6

all doubts cleared.....thank you sir

Bouyouncy and Archimedes principles and thrust and pressure

Sir app physics hamlog Ko reduce syllabus se mat padhao ..... We want full chapter video.🙏🙏🙏🙏🙏💕💕

Conservation of mementum zindagi ka saat bi zindagi ka baad bi

31:09 What will be the Final Answer after (200/43) ??

Sir! Is it necessary to write a unit while solving numerical problem expect in answer

Sir fluid Archimedes principal ❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️👍🙏😭❤️

The best teacher of physics wallah foundation..👏

basically the velocity has to fluctuate in order to conserve momentum.

37:20 Sir it should be 5/3 m/s instead of 10/2 👍👍

Please sir teach archimedes principle relative density

37:27 Sir in question 5 there is mistake , v(5+1) is 6v and if we divide 6v with 10 we get 1.66m /s velocity

37:10 Sir there is a mistake in the question of "an object of mass 1 kg travelling with a velocity of 10m/s" In question 5 you forget to add 1 and 5 together and the common velocity comes to 10/5 means 2 m/s Which was wrong the actual velocity is 1.6 m/s

You are best teacher in physics for us🙏🙏

Ans 3 :- -0.26 m/s Or 0.26m/s towards left. Ans 4 :- -0.4375 m/s Ans 5 :- sir common velocity will be 10/6 not 10/5 because (1+5=6) So final ans is 1.67m/s & Total 'p' before and after the impact = 10kg.m/s

Great teacher ever 🙂

Sir kay ham kg ko gram me convert nhi kar sakte 26:02

Punia sir की आवाज़ मे = ओ सर ए तो हमारे भी exam मे आ रहा है, थैंक उ sir जो आपने इसको explain कर दिए।

Sir 🔝 topic mat katna aap ki hi bharose chal raha he abhi study ❤️❤️❤️❤️❤️

37:18 sir! That is wrong after adding it will become 6 and hence, the answer will be 10/6 i.e, 1.66.. or 1.67approx

Ans. of hockey player =-30/115m/sec. Ans. Of bullet ques.=-0.4375m/sec

Great explain! thankyou sir

Thanks sir for the best explanation.

37:13 sir it will be vc*6 not 5 as 1+5 is 6. and momentum initial will be 10 and final will be 9.6 kgm/s

34:35 *recoil velocity = -0.435m/s*

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40:57 Arre Sir School wali madam se panga lena saloon ka experience hai mera🤣

sir you are great and alots of love to all the pw team

Sir in Q5 masses of both objects will be 6kg(5+1) but you had written 5 kg.

After completing every one chapter from this channel turn our pressure low and make us free .THANK YOU SO MUCH RAKSHAK SIR ❤️😇

Nice Excellent Marvelous Outstanding explanation.

Sir aap bahut achhe padhate hai 👍🙏🙏

Sir at what conditions we find common velocity??

What a teaching sir🥰😍😘✌

Q3: - 0.26 m/s Both will move in left direction as that is depicted by -ive sign

32:46 q3. 0.26ms^-1

32:00 Q3. Given: m1 = 60kg m2 = 55kg u1 = 5 m/s u2 = -6m/s We know that, m1u1 + m2u2 = m1vc + m2vc or, 60×5 + 55×(-6) = vc (60 + 55) or, 300 - 330 = 115vc or, vc = -30/115 or, vc = -6/23 m/s Hence, both the hockey players will move with a velocity of -6/23 m/s after collision in the direction, the second player is facing.