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Important Previous years questions of IIT JEE Part - 1 (In Hindi)
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Through this lesson, you can learn the solution of some advanced level questions which has asked in previous years exams of IIT JEE.

Kumar Ketan is teaching live on Unacademy Plus

Kumar Ketan
#Specialisation in Electronics #6 years teaching experience #Physics Faculty in Kota #"magical education" (211k+ subs) #Writer

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very helpful Abhishek, thanks a lot
sir why are we assuming that after the collision the velocity of the beads remain same??
Kumar Ketan
a year ago
Pls mention the time of doubt
very comprehensive you are a reliable educator on unacademy
Kumar Ketan
2 years ago
very good gjb explaination 😍👌
i don't know how to find momentum plzz explain again
Kumar Ketan
a year ago
  1. PROBLEMS OF COLLISIONS Advanced Level (Asked in IIT JEE)

  2. A large number (n) of identical beads, each of mass m and radius r are strung on a thin smooth rigid horizontal rod of length "L" (L>>r) and are at rest at random position. The rod is mounted between two rigid supports (see figures). If one of the beads is now given a speed "v', the average force experienced by each support after a long time is (assume all collisions are elastic) JEE (Main)Online-2015 2 (L- nr) (L- nr) (c) zero (d) mv2 (L- 2nr)

  3. Fig-a

  4. . Solution: Change in momentum in each collision with rigid support Space between the supports for motion of beads is "L-2nr" Time gap between two successive collision with same support = 2L_4nr 0 2mv

  5. A particle of mass "m" moving in the X- direction with speed "2v" is hit by another particle of mass "2m" moving in the Y- direction with speed "v". If the collisions perfectly inelastic, the percentage loss in the energy during the collision is close to: 1 JEE Main (2015) (a) 56% (b) 62% (c) 44% (d) 50%

  6. Solution: Before collision: 2v Y-axis 2m X-axis Kinetic energy Before collisionm (2v)2+ 2m (v)23mu2

  7. After collision Applying Momentum conservation for inelastic collision 2mv 2 3 101- 22 0) 3

  8. 1 2 2 /2 3 2 4 3 5 3 Ki-K, 3 3mm) 5 5 ~ 56%

  9. This question has statement 1 and statement 2. Of the four choices given after the Statements, choose the one that best describes the two statements Statement-1: A point particle of mass m moving with speed v collides with stationary point particle of mass M .If the maximum energy loss possible is given as f the Statment-2:Maximum energy loss occurs when the particles get stuck together as a result of the collision. n fm M+ m Statement-1 is true, Statement-2 is true, Statement-2 is a correct explanation of Statement-1 Statement-1 is true, Statement-2 is true, Statement-2 is a not correct explanation of Statement-1 Statement-1 is true, Statement-2 is false. Statement-1 is false, Statement-2 is true. 1. 2. 3. 4.