# Easy-acceleration with unit vectors

PEZenfuego

## Homework Statement 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 Thank you for any help

Draco27
So what do we have to find??

PEZenfuego
find the saucer's acceleration in unit vectors and in terms of magnitude and direction.

Staff Emeritus
Homework Helper
Gold Member

## 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?

PEZenfuego
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.

Staff Emeritus
Homework Helper
Gold Member
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

PEZenfuego
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.

Staff Emeritus