Hello,world [PLAIN]http://img507.imageshack.us/img507/4446/samar.jpg [Broken] 1-How does this spring scale work? 2-Where does this increase in the reading of the normal balance(scale) come from? Does it come from the rise in water level in the tank?Okay water already has aconstant mass Does it come from the weight of the ball?I don't think so. 3-why does the apparent weight decreases as the ball goes down into the fluid(by increasing depth)??may be because the buoyant force increases.. the buoyant force is different in case(2) and case(3) although the ball already displaced the same volume of water-so buoyancy should be the same.can you realise my problem here? 4-In case(3) The spring reads zero which means that Fb=Fg so the body should suspend in water instead of sinking ...or may be the spring is exerting a certain force to maintain the ball in this position.may be this question is related to the first one which is concerned with the mechanism of the spring balance 5-can we know from this picture if the spring has a smaller-equal-bigger density than that of water?or it just doesn't indicate?