---
title: "Two blocks of mass M and 3M are in contact on a frictionless horizontal surface. At time t = 0, a horizontal external force F_ext is applied to the block of mass M, as shown in the diagram. The graph shows the magnitude of F_ext as a function of time t. Which of the following is a correct expression for the magnitude of the impulse delivered to the block of mass 3M by the block of mass M during the time interval from t = 0 to t = Delta t?"
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url: "https://nerd-notes.com/ubq/110258/"
date_modified: "2026-04-01T02:41:41+00:00"
---

# Two blocks of mass M and 3M are in contact on a frictionless horizontal surface. At time t = 0, a horizontal external force F_ext is applied to the block of mass M, as shown in the diagram. The graph shows the magnitude of F_ext as a function of time t. Which of the following is a correct expression for the magnitude of the impulse delivered to the block of mass 3M by the block of mass M during the time interval from t = 0 to t = Delta t?

Two blocks of mass M and 3M are in contact on a frictionless horizontal surface. At time t = 0, a horizontal external force F_ext is applied to the block of mass M, as shown in the diagram. The graph shows the magnitude of F_ext as a function of time t. Which of the following is a correct expression for the magnitude of the impulse delivered to the block of mass 3M by the block of mass M during the time interval from t = 0 to t = Delta t?

![A physical diagram showing two rectangular blocks in contact on a horizontal surface. The left block is labeled M and the right block is labeled 3M. A horizontal vector arrow labeled F_ext points to the right, pushing against the left face of the block of mass M.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1775011300-HdNq8o.jpg)

![A graph of Force F_ext vs. time t. The vertical axis is labeled F_ext and the horizontal axis is labeled t. A horizontal line segment is drawn at a height of F_0 starting from the vertical axis (t = 0) and ending at t = Delta t. A vertical dashed line connects the end of the segment to the t-axis.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-2-1775011301-DLKZpV.jpg)

- **A.** \(F_0 \Delta t\)
- **B.** \(\dfrac{3}{4} F_0 \Delta t\)
- **C.** \(\dfrac{1}{4} F_0 \Delta t\)
- **D.** \(\dfrac{1}{3} F_0 \Delta t\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/110258/*