# Problems with vectors

1. Apr 1, 2012

### blob84

1. The problem statement, all variables and given/known data
In an assembly operation illustrated in Figure P1.49, a ro-bot moves an object ﬁrst straight upward and then also tothe east, around an arc forming one quarter of a circle of radius 4.80cm that lies in an east–west vertical plane. Therobot then moves the object upward and to the north,through a quarter of a circle of radius 3.70cm that lies in anorth–south vertical plane. Find (a) the magnitude of thetotal displacement of the object and (b) the angle the totaldisplacement makes with the vertical.
http://img62.imageshack.us/img62/2459/assemplaggio.jpg [Broken]

2. Relevant equations

3. The attempt at a solution
$$C_{1}/4=2πr=2π(4.80cm)/4=7.55$$
$$A^→=(7.55,0)cm$$
$$C_{2}/4=2πr=2π(3.70cm)/4=5.81$$
$$B^→=(0, 5.81)cm$$
$$R^→=A^→+B^→=(7.55, 5.81)cm$$
$$R=sqrt(7.55^2+5.81^2)=9.52cm$$
$$σ=37.6°$$;
the results is 10.4 cm and 35.5°.

Last edited by a moderator: May 5, 2017
2. Apr 1, 2012

### pongo38

Your C1 and C2 appear to be curved lengths. Does Pythagoras theorem apply to curved lengths?

3. Apr 1, 2012

### blob84

no, but i have no idea how to solve.

4. Apr 1, 2012

### dikmikkel

How about applying a spherical polar coordinate system and integrate over a line describing the path i.e. do two seperate integrations and add them up.