No question that it's simple, but for some reason I can't fully understand this. I stumbled upon this problem asking "If we put a glass of water on a digital weighing scale and we reset the scale to zero, after which we submerge a cube of an unknown material in the water attached to a string (like on the picture attached), the number on the scale will be:" a) equal to zero b) different from zero and give information about its volume c) different from zero and give information about its mass d) different from zero and give information about its weight I presumed the answer was a, as the cube is still suspended on a string, meaning the force of gravity should be canceled out by the upward muscle force (or whatever is holding the string), so I thought there shouldn't be any force acting down, onto the scale. But it turned out to be answer b. It probably has to do with water being shifted up, but I can't figure it out exactly. Quite frustrating, as it should be a simple question. Any help?