An object's two dimensional velocity is given by v(t) = ( sqrt(3t)-t , t^2-5t). What is the object's rate and direction of acceleration at t=2 ?

1 Answer
Apr 14, 2017

The rate of acceleration is =1.07ms^-2 in the direction =248.7º

Explanation:

The acceleration is the derivative of the velocity.

a(t)=v'(t)

v(t) = < sqrt(3t)-t , t^2-5t>

a(t)= < sqrt3*1/(2sqrtt)-1,2t-5>

When t=2

a(2) = < sqrt3*1/(2sqrt2)-1,2*2-5 >

=< -0.39,-1 >

The rate of acceleration is

=||a(2)||

=||< -0.39,-1 >||

=sqrt((0.39)^2+(1)^2)

=1.07ms^-2

The direction is in the 3rd quadrant

theta=180+arctan(1/0.39)

=248.7º