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A particle is thrown upwards from ground...

A particle is thrown upwards from ground. It experiences a constant resistance force which can produce a retardation of `2 ms^-2.` The ratio of time of ascent to time of descent 13 (`g = 10 ms^-2`)

A

`1:1`

B

` sqrt((2)/(3))`

C

` (2)/(3) `

D

` sqrt( (3)/(2) ) `

Text Solution

Verified by Experts

The correct Answer is:
B
Let initial velocity =u
Ascent : accleration =`g+2=12 m//s ^(2) `
Time of ascent `= (u)/(12) ` and max . Height `=h=(u^(2))/( 2 xx 12 ) =(u^(2))/(24) `
Descent : acceleration `= g-2=8m//s^(2) `
Time of descent =` sqrt (( 2h)/( 8)) =sqrt (( 2 xx (u^(2))/(24) )/(8)) =( u)/( 4sqrt6) " "," " "Ratio "=( "Time of asscent ")/("Time of descent ") =sqrt(( 6)/( 3)) =sqrt(( 2)/(3))`
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