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title: "A block of weight \\( W \\) is floating in water, and one-third of the block is above the surface of the water. Which of the following correctly describes the magnitude \\( F \\) of the force that the block exerts on the water and explains why \\( F \\) has that value?"
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url: "https://nerd-notes.com/ubq/79348/"
date_modified: "2025-03-04T12:15:47+00:00"
---

# A block of weight \( W \) is floating in water, and one-third of the block is above the surface of the water. Which of the following correctly describes the magnitude \( F \) of the force that the block exerts on the water and explains why \( F \) has that value?

A block of weight \( W \) is floating in water, and one-third of the block is above the surface of the water. Which of the following correctly describes the magnitude \( F \) of the force that the block exerts on the water and explains why \( F \) has that value?

- **A.** \( F = \frac{2}{3} W \). Only two-thirds of the block is in contact with the water, so it will exert a force on the water equal to two-thirds of the block’s weight.
- **B.** \( F = \frac{2}{3} W \). The water exerts a force on the block equal to the weight of the part of the block that is underwater. The block then exerts a force of equal magnitude on the water.
- **C.** \( F = W \). The block is at rest, so the net force on it must be zero. The water must exert an upward force of magnitude \( F \) on the block to make this so. The block then exerts a force of equal magnitude on the water.
- **D.** \( F = W \). Any object will always exert a force on the surface beneath it that is equal to the weight of the object.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/79348/*