An object's two dimensional velocity is given by v(t) = (3t-sqrtt , 2t-4 ). What is the object's rate and direction of acceleration at t=a ?

1 Answer
Mar 12, 2017

The rate of acceleration is =sqrt(13-3/sqrta+1/(4a)) in the direction =arctan((4sqrta)/(6sqrta-1))

Explanation:

v(t)=(3t-sqrtt,2t-4)

The acceleration is the derivative of the velocity

v'(t)=(3-1/(2sqrtt),2)

Therefore,

v'(a)=(3-1/(2sqrta),2)

The rate of acceleration is

||v'(a)||=sqrt((3-1/(2sqrta))^2+ 4)

=sqrt(9-3/sqrta+1/(4a)+4)

=sqrt(13-3/sqrta+1/(4a))

The direction is

=arctan(2/(3-1/(2sqrta)))

=arctan((4sqrta)/(6sqrta-1))