If a particle of mass m start from along curved circular path shown in figure with constant tangential acceleration a, then net force at B on the particle has the magnitude :

Options

A. zero
B. `2ma sqrt(1 + pi^(2))`
C. `ma sqrt(1 + pi^(2))`
D. `ma pi sqrt(1 + pi)`

Answer

C

Explanation

`F_("net") = ma_("total") = m sqrt(a_(t)^(a) + a_(c )^(2))`
`a_(t) = a`
`a_(c ) = (v^(2))/(R )`
`v^(2) = 0 + 2a ((pi R)/(2))`
`u = sqrt(pi R a) " " rArr a_(c ) = (pi R a)/(R ) = pi a`