SAT Subject Physics Practice Question 550: Answer and Explanation
6. Three ice cubes are placed into three equal beakers filled with water. One ice cube has a mass of 50 g, the second ice cube has a mass of 75 g, and the third ice cube has a mass of 100 g. After the ice cubes are added, each beaker is filled to the brim with water at a temperature of 1°C. After a period of time passes and all three ice cubes melt, which of the following situations is most likely?
A. All three beakers have overflowed.
B. None of the beakers have overflowed.
C. The beaker with the 100 g ice cube has overflowed.
D. The beakers with the 100 g and the 75 g ice cube in them have overflowed.
E. The beaker with the 50 g ice cube has overflowed.
Correct Answer: B
The correct answer is (B). When water freezes, it becomes less dense. Therefore, when ice cubes are placed into liquid water, they displace a volume of water equal to their weight. When the ice melts no further, volume is added to the container.