Question

13.33 Figure 13.33 shows a 100 g block of copper and a 100 g block of aluminum. connected by a massless string that runs over two pulleys. The two blocks exactly balance, since they have the same mass. Now suppose that the whole system is submerged into water. What will happen? A. the copper block will fall, the Aluminum block will rise B the aluminum block will fall and the copper block will rise

C nothing will change
D both blocks will rise

Answer 1

When submerged in water, the aluminum block will fall and the copper block will rise due to the aluminum's lower density and greater displacement of water, leading to a larger buoyant force acting on it compared to the more dense copper block.

Step-by-step explanation:

When the 100 g block of copper and the 100 g block of aluminum are submerged in water, we need to consider the concept of buoyancy. Buoyancy is a force that acts on objects submerged in a fluid, opposing the weight of the submerged object. Since both blocks have the same mass, under normal conditions, they balance each other. However, the key to solving this question is the concept of density.

Copper has a higher density than aluminum, and therefore it displaces less water than aluminum when submerged. This results in a larger buoyant force acting on the aluminum block, as it displaces more water relative to its weight. Hence, the buoyant force will be stronger on the aluminum block than on the copper block. According to Archimedes' principle, an object submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the object.

Therefore, option B is correct: the aluminum block will fall and the copper block will rise, because the buoyant force is greater on the less dense aluminum, making it effectively lighter in the water.