The tension in a string holding a solid block below the surface of a liquid (of density greater than that of solid) as shown in figure is `T_(0)` when the system is at rest. What will be the tension in the string if the system has an upward acceleration a?
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Options

A. ` T ( 1 - (a )/(g)) `
B. ` T ( 1 + (a)/(g)) `
C. ` T ((a)/(g) - 1 ) `
D. ` (a)/(g) T `

Answer

B

Explanation

When system is at rest:
`T=B-mg=Vrho_(1)g-(Vpg)=V(rho_(1)-rho)g" "...(i)`
Where `rho_(1)` = Density of liquid and `rho` = Density of block
If system is moving upward with acceleration a: `B'-mg-T'=maRightarrowVrho_(1)(g+a)-Vrho(g+a)=T'`
`T'=V(rho_(1)-rho)(g+a)" "...(ii)` From (i) and (ii) `T'=T(1+(a)/(g))`