The deceleration exerienced by a moving motor blat, after its engine is cut-off is given by `dv//dt=-kv^(3)`, where `k` is constant. If `v_(0)` is the magnitude of the velocity at cut-off, the magnitude of the velocity at a time `t` after the cut-off is.

Options

A. `v_(0)/(sqrt((2v_(0).^(2)kt+1)))`
B. `v_(0)e^(-kt)`
C. `v_(0)//2`
D. `v_(0)`