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Easy-acceleration with unit vectors

  • Thread starter PEZenfuego
  • Start date
  • #1
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Homework Statement



untitled.jpg


r1=(0m)
r2=(2000i + 1000j)m
v1=(200j)m/s
v2=(200i-100j)m/s

Homework Equations


tantheta=vy/vx

v2^2=v1^2+2ax
v2=v1+at
x2=x1+v1t+1/2at^2

The Attempt at a Solution



IMG_20120909_150513.jpg


Thank you for any help
 

Answers and Replies

  • #2
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So what do we have to find??
 
  • #3
48
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find the saucer's acceleration in unit vectors and in terms of magnitude and direction.
 
  • #4
SammyS
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Homework Statement



View attachment 50618

r1=(0m)
r2=(2000i + 1000j)m
v1=(200j)m/s
v2=(200i-100j)m/s

Homework Equations


tantheta=vy/vx

v2^2=v1^2+2ax
v2=v1+at
x2=x1+v1t+1/2at^2

The Attempt at a Solution



View attachment 50617

Thank you for any help
Are those kinematic equations for components of vectors, or for vectors themselves?
 
  • #5
48
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Are those kinematic equations for components of vectors, or for vectors themselves?
If you click the first picture, you will have an understanding equal to mine. I'm sorry.
 
  • #6
SammyS
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If you click the first picture, you will have an understanding equal to mine. I'm sorry.
Sorry for the slow response.

I should have been more direct with my earlier response.

The set of kinematic equations you have
(v2)2=(v1)2+2ax
(v2)=(v1)+at
x2=x1+(v1)t+1/2at2
are valid for each component of displacement, velocity, and acceleration.

So you have two such sets of kinematic equations:
(v2)x2 = (v1)x2 + 2axx
(v2)x = (v1)x + axt
x2 = x1 + (v1)xt + 1/2axt2

(v2)y2 = (v1)y2 + 2ayy
(v2)y = (v1)y + ayt
y2 = y1 + (v1)yt + 1/2ayt2
 
  • #7
48
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Sorry for the slow response.

I should have been more direct with my earlier response.

The set of kinematic equations you have
(v2)2=(v1)2+2ax
(v2)=(v1)+at
x2=x1+(v1)t+1/2at2
are valid for each component of displacement, velocity, and acceleration.

So you have two such sets of kinematic equations:
(v2)x2 = (v1)x2 + 2axx
(v2)x = (v1)x + axt
x2 = x1 + (v1)xt + 1/2axt2

(v2)y2 = (v1)y2 + 2ayy
(v2)y = (v1)y + ayt
y2 = y1 + (v1)yt + 1/2ayt2
It makes sense now. thank you.
 
  • #8
SammyS
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It makes sense now. thank you.
What did you get for answers?
 

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