A particle P moves such that its position vector r with respect to the origin O at the time t is given by
r = cos3ti + sin3tj
a) Find an expression for v, the velocity of P at time t.
b) Show that the direction of v is perpendicular to that of r for all values of t.
c) Find the speed of P.
OK for part a I'm assuming you differentiate r which i get
v = -3sin3ti + 3cos3tj
is this correct??Part b Im stumped with, not sure I've learned that.
For part c i think maybe i use equation v=u+at ??
if so how could i find t ?
For part b) we know that if two vectors are perpendicular that the dot product is zero... so
Originally Posted by djmccabie
Speed is the magnitutde of velocity so...
thanks pal. Did i do part a correctly?