Tangent line to a particles path at a specific time?

  • #1
badtwistoffate
81
0
how do you find orientation of a line that is tangent to the particle's path at t = 2.10 s?(from the +x axis)
before this i found the position r of a particle moving in an xy plane is given by r = (1.00t3 - 8.00t) i + (7.00 - 4.00t4) j.
So I found r,v,a, for t=2.10s (all in m)
r=-7.54 i +-70.8 j
v=5.23 i + -148 j
a=12.6 i + -212 j
i first tried using v's i and j to make a triangle and find the angle from that by inverse tan (-148/5.23) and got -87degress or -212 but that was wrong...
any help?
 

Answers and Replies

  • #2
Leong
382
2
i got 272 degree from the + x-axis in anticlockwise direction.
 
  • #3
badtwistoffate
81
0
how did u get that?
did you just do the inverse tan and adding to 360? does that make sense?
 
  • #4
Leong
382
2
your v lies in the fourth quadrant.
 

Suggested for: Tangent line to a particles path at a specific time?

  • Last Post
Replies
13
Views
411
Replies
5
Views
394
Replies
40
Views
1K
  • Last Post
Replies
28
Views
570
Replies
3
Views
432
Replies
3
Views
446
Replies
4
Views
226
Replies
8
Views
323
Top