11hmmmm...ok got it...thanks...
some one with the 1st one pls...
A Long pliablle carpet is laid on ground. One end of the carpet is bent back and pulled backwards with a constant velocity of 16 m/s. If mass/length of the carpet is 1 Kg/m , the minimum force required to pull the carpet is :
a) 4 N b) 8 N c) 16 N d)128 N
Please give a detailed solution....The ans given is d) 128 N.
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A cart containing sand is moving under the action of a constant force F. A hole is opened at the bottom so that sand flows out at constant rate \mu kg/s. If the velocity of the cart at any instant is v then the thrust force due to this change of mass is :
a) \mu v b) \mu v2 c) F - \mu v d)Zero.
The ans given is d) zero....Shudn't it be a
please give a detailed solution...
will be adding more....
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3 Answers
1for the second question
the mass is falling in the downward direction initially leaving with zero velocity.
note: that the cart has velocity in the horizontal direction.
since since relative to the cart the leavng mass has zero relative velocity there is no thrust.
11
1the first one was solved by eureka ,i had asked it as doubt
please refer
http://www.targetiit.com/iit-jee-forum/posts/from-kaymant-sir-s-archive-12030.html
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