A particle is moving on a straight line and its distance `x` cms from a fixed point `O` on the line is given by`x=sqrt(t^(2)+1)` then the velocity of particle at `t=1` is

If a particle moving in a straight line and its distance x cms from a fixed point O on the line is given by x=sqrt(1+t^(2)) cms, then acceleration of the particle at t sec. is

A particle moves in a straight line, so that after t second, the distance x from a fixed point O on the line is given by x=(l-2)^(2)(t-5) . Then

A particle is moving in a straight line so that after t seconds its distance is s (in cms) from a fixed point on the line is given by s= f(t)=8t+t^3. Find the velocity at time t= 2sec (ii) the initial velocity can acceleration at t=2 sec