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4 Oct 2009 20:48:19 IST

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.....answer this conceptual question on Newton's laws of motion....

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.....answer this conceptual question on Newton's laws of motion....

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ultimatum

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4 Oct 2009 20:50:53 IST

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Rajat Ranjan

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4 Oct 2009 20:57:34 IST

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the upper part should break first because the force on the upper string is more than the lower part i.e. F+mg>F.

ultimatum

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4 Oct 2009 20:59:53 IST

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what if i say the lower part breaks first!!!!

Rajat Ranjan

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4 Oct 2009 21:02:02 IST

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why so??

ultimatum

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4 Oct 2009 21:09:33 IST

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which string is breaking is depending on how are u pulling the lower rope.....if u pull instantaneously the lower string is breaking and if u are pulling slowly then the upper string is breaking......that is what i am unable to understand why?????

PANKAJ KUMAR

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4 Oct 2009 21:18:19 IST

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if u pull it wid a jerk.......the string immediately reaches its breaking strength nd spring breaks at d point nearest to pt of action....

nd if u pull it slowly.....it wil break frm above as d tension is more on the upper side....

ultimatum

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4 Oct 2009 21:18:44 IST

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....can anyone explain??????????????

sarthak verma

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4 Oct 2009 21:19:21 IST

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it is due to a sudden impulse when we apply an instantaneous force to a pulley, it breaks the lower string first, but due to applying forces steadily,the upper part breaks first, and also the condition for which string will break first will also depend on F, if F>>mg, then the lower string will break first..., since F+mg = F if F>>mg

spiderman

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4 Oct 2009 21:45:48 IST

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as wire are same both have same value of ultimate stress..when force is applied steadly..it rises frm 0 to max value..in this case the upper portion tension will always be greater than lower bt Mg value..so upper string breaks first...but when the force is applied suddenly the forces are not able to reach upper wire(before it happens lower wire breaks)..its only the lower one which sustains it.and gets break.

edison

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5 Oct 2009 13:55:21 IST

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If upper and lower strings are exactly alike and are made up of same material then Upper string will break first.

This is because when force F is applied on lower string and is increased then it is the upper string that first reaches the tension that corresponds to its breaking point as tension inupper string = T = F + mg

wHaT tHe F

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5 Oct 2009 14:41:54 IST

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LOlz ....i knw where did gaurang sinha got this stuff frm ...its MIT video lectures .......

btw @ edison sir .......the upper string wont break always............

if string is pulled vry fast , lower one breaks 1st, if it is pulled slowly ...upper one breaks first ......

i too donno d exact reason .. but rahul kumar's ans looks satisfactory ..but it may or may not be d correct one .........

djdylan2000. bits goa eee

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5 Oct 2009 15:07:23 IST

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If u pull with a jerk, the lower string will break first, because the mass tends to stay where it is to some extent due to inertia... when u pull slowly, the top string will break cuz of more tension.

Priyak Dey

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5 Oct 2009 16:16:18 IST

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If the string is given a sudden force, i.e, an impulse is given wich exceeds the max. breaking tension of the string the lower string will break first...Because due to sudden impulse for a moment the mass tends to remain in rest for inertia of rest while the string detaches itself from the mass......

But if force is applied with a gradual increase in magnitude.the upper string will break first...the force acting on the upper string will be F=Mg>F(force acting on lower string)...........

Cherrzzzzzzzzz BROTHER.........

PLZ rate me IF YOU FIND MY ANS USEFUL N REASONABLE.........

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