An object's two dimensional velocity is given by v(t) = ( 1/t, t^2)v(t)=(1t,t2). What is the object's rate and direction of acceleration at t=2 t=2?

1 Answer

The acceleration at t=2t=2 is a(t) = (-1/4, 4)a(t)=(14,4), whose absolute value is sqrt257/42574 and the direction is 93.576^@93.576 w.r.t. xx-axis.

Explanation:

Acceleration is the first derivative of velocity, so if we differentiate the velocity function, we get a function for the acceleration:

(dv)/(dt) = (-1/t^2, 2t)dvdt=(1t2,2t)

Inserting t=2t=2 gives us the acceleration at t= 2st=2s, namely

a(t) = (-1/4, 4)a(t)=(14,4), whose absolute value is sqrt((-1/4)^2+4^2)=sqrt(257/16)=sqrt257/4(14)2+42=25716=2574

The direction is given by alpha=tan^(-1)(4/(-1/4))=tan^(-1)(-16)=93.576^@α=tan1(414)=tan1(16)=93.576 w.r.t. xx-axis.