How to apply impulse on chipmunk body on a specific direction?

Question

i am using:

 cpVect vector1=cpv(angle, 400);

 [body applyForce:vector1 offset:vector1];

but this not working well as needed to put a correct angle using touch screen below line of code used for getting angle

-(void)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    for( UITouch *touch in touches )
    {
        CGPoint location = [touch locationInView: [touch view]];
        location = [[CCDirector sharedDirector] convertToGL: location];
        float angleRadians = atanf((float)location.y/ (float)location.x-1);
        float angleDegrees = CC_RADIANS_TO_DEGREES(angleRadians);
        float cocosAngle = -1 * angleDegrees;
       angle = angleDegrees + 30;
    }
}

Answer 1

Thanks to you all for your precious time to give on that. Finally i found the way to achieve impulse on a chipmunk body on a specific direction. Now i am using below code.

 **angle = angle-90;                  //angle from cctouchesMoved function
 float magnitude=shootPower;        // magnitude range between 200 to 1000
 cpVect impulse = cpv((cos(angle) * magnitude) , -(sin(angle) * magnitude));

 [body applyImpulse:impulse offset:cpvzero];**

// applyImpulse gives the right way for putting impulse as needed using above sin and cos theta values.