An object's two dimensional velocity is given by v(t) = ( sin(pi/3t) , 2cos(pi/2t )- t )v(t)=(sin(π3t),2cos(π2t)t). What is the object's rate and direction of acceleration at t=5 t=5?

1 Answer
Jan 4, 2018

The rate of acceleration is =4.17ms^-2=4.17ms2 in the direction 97.2^@97.2 anticlockwise from the "x-axis"x-axis

Explanation:

The acceleration is the derivative of the velocity

v(t)=(sin(pi/3t),2cos(pi/2t)-t)v(t)=(sin(π3t),2cos(π2t)t)

The acceleration is

a(t)=v'(t)=(pi/3cos(pi/3t), -pisin(pi/2t)-1)

When t=5

a(5)=v'(5)=(pi/3cos(pi/3*5), -pisin(pi/2*5)-1)

=(0.52, -4.14)

The rate of acceleration is

||a(5)||=sqrt((0.52)^2+(-4.14)^2)=4.17ms^-2

And the direction is

theta=arctan(-4.14/0.52)=97.2^@ anticlockwise from the "x-axis"