# Physics problem involving displacement of car!

1. May 24, 2012

### wbetting

1. The problem statement, all variables and given/known data

A car is driven east for a distance of 48 km, then north for 25 km, and then in a direction 33° east of north for 29 km. Determine (a) the magnitude (in km) of the car's total displacement from its starting point and (b) the angle (from east) of the car's total displacement measured from its starting direction.

2. Relevant equations
magnitude is sort of a^2+b^2
direction is tan theta = ay/ax

3. The attempt at a solution
I got part a right by finding magnitude of "R" which was sqrt of 62.5^2+50.11^2= 80.11 km i just can't seem to get part b right. i know it is north of east but whenever i do inverse tan of 50.11/62.5 i get 38.72 degrees which is wrong, HELP please

2. May 25, 2012

### tiny-tim

welcome to pf!

hi wbetting! welcome to pf!
no you didn't, you just got close

you used 30° instead of 33° !

3. May 25, 2012

### wbetting

It marked it right on my online homework. Any idea how to do part b?

4. May 25, 2012

### tiny-tim

but you used 30° instead of 33° !