A pebble is dropped into a graduated cylinder with 20ml of water in it. After the pebble is dropped in, it sinks and the water level rises to 25ml. What is the volume of the pebble? (Numbers and Units!)
I did 25ml - 20ml but the answer had to be something about density.
To find the volume of the pebble, we can use the concept of displacement. When an object is submerged in a fluid, it displaces an amount of fluid equal to its own volume. The difference in volume before and after the pebble is dropped in corresponds to the volume of the pebble.
In this case, the water level rose from 20ml to 25ml, implying that the pebble displaced 5ml of water. Therefore, the volume of the pebble is 5ml.