How do I get to know what sprite has been touched?

I have some sprites coming from the bottom of the screen in a random order. I want to swipe the sprite in the direction of the swipe. I got the algorithm for swiping. Also, I get an NSLog message whenever any sprite has been touched in the screen. The NSLog gives correct responses to any and every object touched. But how do I know which sprite has been swiped to write the code for applying impulse to that particular sprite?

I am trying the following code:

               SKNode *sprite = [self nodeAtPoint:location];
               [ball.physicsBody applyImpulse:CGVectorMake(dx, dy) atPoint:location];
               [self addChild:sprite];

Also,

userInteractionEnabled = YES for all the sprites

And all the sprites are performing an action (Just in case this is the reason why I cannot swipe them while they are already running an action, in this case what else should I use to move the sprites?)

Sorry if this is too dumb, I am a noob

Thanks in advance!