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

1 Answer
Sep 26, 2016

The vector is a(t) = ((1/2)(t - 2)^(-1/2) - 1, 2t) Substitute 3 for t, and then compute the magnitude and direction as you would any vector.

Explanation:

a(3) = ((1/2)(3 - 2)^(-1/2) - 1, 2(3))

a(3) = (-1/2, 6)

The rate of acceleration is the magnitude:

|a(3)| = sqrt((-1/2)^2 + 6^2)

a ~~ 6.02 (units)/s^2

theta = tan^-1(6/(-1/2))

theta ~~ -85.2°