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What is the result when î + 14ĵ is multi...

What is the result when î + 14ĵ is multiplied by √49?
a) 7î + 98ĵ
b) 98î + 14ĵ
c) 7î + 98ĵ
d) (î + 7ĵ)*√49

Text Solution

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Let `0(0,0) be the orign of the system. Each brick is of mass M and length L, Each brick is displaced w.r.t one in contact by `L/10`.

`:. The X coordiN/Ate of the centre of mas `X_(cm)`
=1/{7mL/10)^((mL)/2+m(L/2+L/10)+.......+m(L/2)}`/(7mL/10)`
`X_(cm)=(L/2+L/2+L/10+L/5+L/2+(3L)/10+L/2+L/5+L/2+L/10+L/2)/7`
`=(7L/2+5L/10+2L/5)/7=(22L)/35`
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