Advance Illustrations – Sliding on a Conveyer Belt | Work Energy Power #17 for JEE Advanced

Questions asked in JEE Advanced are based on critical thought processes rather than direct application of concepts. For preparation of JEE Advanced, students have to focus on problems based on multi concept applications.

Ashish Arora Sir has taken up a case of Sliding on a Conveyer Belt which is important for select in IIT. Work Energy Power is chapter 6 of Class 11 NCERT and is crucial in JEE preparation. These advanced illustrations cover all formulas and relevant solved examples from Work Energy Power and are useful for making notes for IIT JEE preparation.

#jeeadvance #jeephysics #pg4AdvIllustrations #wep4jee #workenergypower #workpowerenergy

[yashijainj]

every question has sumthing new to learn....thanks a lot..!

[vikasnarang]

Most of us don't recommend this channel to our friends because it is so damn good, thanks sir ....

[alexs]

wow this question is really mind digging...

[advaitzambre]

my mind is always blown after seeing you solve the questions, which seems though while approaching, but once getting gist of it, one can understand all the steps and knows the reasons behind all the steps

[tsamrawat]

In belt frame which is inertial, we use
V relative intially = v+ v not
V relative final= 0
Work done by friction = change in kinetic energy= O - 1/2 m ( v+ v not ) ^2
Put the value of v not and we get the same result.
Is it correct?

[adarshchaturvedi]

heat dissapated should be max. hence final speed is zero .. is this because after that friction will start dissipating heat again and hence dissipation of heat increases?

[anuragupadhyay]

Jab block rest pe aaya uske niche ka ground abhi bhi "v" se move Kar Raha aur block abhi bhi rest par hai to rubbing hogi with belt heat will be produced
Now due to friction block bhi aage move karna start karega lekin abhi bhi belt is moving with more velocity to rubbing hogi tab tak jab tak block ki velocity belt ki velocity ke barabar na ho jaye Wahi sir ne Mana hai ki let l1 pe block ki velocity v ho gayi

[yashshende]

Go in the relative frame of conveyor belt and see the magic
Question will be done very quick..

[harryh]

Sir in the 2nd motion work is done by friction to increase the kinetic energy of block so heat should not be dissipated due to block motion, it should be only due to opposing belt motion therefore no umgl term should be there in 2nd case

[deepamshah]

I already took 1½hr on this still there are some doubts which is not cleared
1) the entire question is solved from which frame (ground or belt)?
2) if its ground frame then in the first part we take displacement as the lenght of conveyor belt 'L' but while calculating heat dissipated by friction we took displacement as L+vt1 & vt2-L1 why??

[mohitnayak]

sir, i didn't understand the part where you wrote about the total work done by friction.

[tomtywin]

Sir, do two digit rankers in JEE ADVANCED, solve these kind of problems on their own for first time?

[Devil]

Sir, if I put coeff of friction as 0 in the obtained result then also we get heat dissipated as non zero.But how is the energy dissipated without a non conservative force present here ??

[bios]

So, work done by friction is -μmgl in ground frame, but -μmg(l+vt1) in belt frame as the total length of action of friction in ground frame and belt frame are l and l+vt1?
, i.e., is the work done by friction different in different frames of references?
also, would that explain why the kinetic energy drops from muu/2 to 0 as seen from ground frame of reference and from m(v+u)(v+u)/2 to mvv/2 as seen from belt frame as the friction does more work in the belt frame than ground frame? if yes, would the heat dissipated against friction be different in the two frames?

[SumaidSyed]

Sir, how do we know that l1<l? I mean isn't it possible that in second part velocity of block will not reach to v but length will come to end?

[RoshanSharma-movy]

These questions are very difficult. I feel demotivated when I can't solve them on my own.

[shashipandit]

??? Sir, in 1st equation , for calculating work done by friction, you used absolute distance travelled by the block . But in last equation, for calculating work done by friction , you used relative distance travelled by block???Why sir???

[gouravgupta]

how relative displacement of block wrt belt is v(v/ug) -l ???

[kunalkumar]

Why will the block move with a speed different than speed of conveyer at L1?

[adarshchaturvedi]

sir when we are analysing w.r.t conveyer belt then v0+v will be the required velocity of projection na ?