Grade 11Mechanics

a 10 kg boy standing in a 40 kg boat floating on water is 20 metre from the shore of the river . if he moves 8 metre on the boat towards the shore , then how far is he now from the shore ? assume no friction between boat and water

Aashray Vinayaka

10 Years agoGrade 11

2 Answers

vinay

10 Years ago

To keep center of mass at rest as to net exrernal force is zero so the boy would move 8-x displacement and boat would move x displacement on the opposite direction so

$10*(8-x)=40*(x) so, x=1.6m$

$8-1.6 = 6.4m$

so,

distance from boat = $20-6.4=13.6m$

Harshil

7 Years ago

10 (8)=(40+10)×y

y=1.6

distance of boy=20-8+1.6

=13.6

First the boy run 8m towards shore but the boat moves back by some distance y.so the displacment will not be 12 but 12+y

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a 10 kg boy standing in a 40 kg boat floating on water is 20 metre from the shore of the river . if he moves 8 metre on the boat towards the shore , then how far is he now from the shore ? assume no friction between boat and water

Aashray Vinayaka

2 Answers

vinay

Harshil

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