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Adding î + 77ĵ and 7î + ĵ gives a) 8î ...

Adding î + 77ĵ and 7î + ĵ gives ______
a) 8î + 78ĵ
b) 0î + 76ĵ
c) î + 74ĵ
d) 78î + 8ĵ

Text Solution

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A ball of mas m is dropped to a floor from a cetain height let h
`:. v_1=sqrt(2gh)`
`v_1=0`
`v_2=-sqrt(2gh)`
`v_2=0`
`:. Rate of change of velocity
F=(mxxw2sqrt(2gh))/t`
`:. V=sqrt(2hg)s=h, u=0`
`rarr sqrt(2gh)=gt`

`t=sqrt(2h)/g`
`:. Total time =2sqrt(2h)/g`
`:. F=(mxx2sqrt(2gh))/(2sqrt((2h)/g))=mg`
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