- #1
unscientific
- 1,734
- 13
Homework Statement
(a) Show that if three vectors a, b and c are linearly dependent then
a[itex]\bullet[/itex](b x c) = 0
(b)Two particles are on the trajectories: r = a + ut and r = b + vt. Show that the particles will collide if v[itex]\bullet[/itex](b x u) = v[itex]\bullet[/itex](a x u).
(c) Express the time for the collision in terms of a, b, u and v.
(d) Hence or otherwise, show that the collision takes place at position
r = b + v [a [itex]\bullet[/itex] (b x u)/v [itex]\bullet[/itex] (b x u)]
(e) What must the time of collision be if a, b, u and v are coplanar?
Homework Equations
The Attempt at a Solution
(a) Shown.
(b) shown.
(c) shown.
(d) shown.
(e) this meant a [itex]\bullet[/itex] (b x u) = v [itex]\bullet[/itex] (b x u) = 0
Then what i have is t = 0/0 which doesn't make sense..
Not sure what difference does co-planar make to the question, as parts (a) to (d) never worked under the assumption that the vectors are co-planar. Does it impose some sort of restriction?