# Forces and Newton's Laws with vectors help

1. Jan 7, 2009

### delfam

1. The problem statement, all variables and given/known data
One force of 60N and a second of 30N act on an object at point P. Graphically add the vectors and find the magnitude of the resultant when the angle between them is as follows.

a. 0 b. 30 c. 45 d. 60 e. 90 f. 180

2. Relevant equations
A-Sin A = B/Sin B = C/ Sin C
pythagorean theorum
F=ma

3. The attempt at a solution
I have no clue where to start

2. Jan 7, 2009

### LowlyPion

Welcome to PF.

A force is a vector. [magnitude,direction]

The question is basically asking you to add vectors.

When 2 vectors are in the same direction then of course you just add the magnitudes and the result is the sum in the same direction.

b) asks you to add 2 vectors that are 30° to each other, so ...

3. Jan 7, 2009

### delfam

so how would i find 30 degrees, do I use the laws of sine or cosine

4. Jan 7, 2009

### LowlyPion

The Law of Cosines should do it.

http://quarknet.fnal.gov/toolkits/ati/vectors.html