Well TS, it seems that I made a mistake for part C. I used the
formula for circular motion directly without realising that only
the tangential acceleration = v^2/r. And to find tangential
acceleration is pretty tedious in this case. But it can be done.
Alternatively
a) You want to find the radius of curvature.
b) You know that the radius vector is perpendicular to the
vector of the velocity.
so
1) Find the velocity vector in terms of magnitude and direction.
Magnitude given by sqrt( vx^2 + vy^2). Angle(direction) given by
arctan(vy/vx).
2) Find the direction perpendicular to the velocity vector. It
actually gives you the direction of the radius vector.
3) So you need to find the magnitude of the radius vector.
Simple. You now have the angle and the horizontal distance of P
from the origin (your x value basically).
4) Construct the basic right angled triangle and use cosine to
find the magnitude of the radius.
A bit busy with my exams preparation or I would try to upload a
peekture. It's probably university first year question.. either
that or I'm trying too hard.
ok... im having problems already :s
@ Part 4)
not sure how it looks like or what values to use