Cradle Collisions Worksheet
Physical Science • Energy Transfer
Reading Comprehension
Molecule Collisions & Newton's Cradle
Article Analysis
Name:
Date:
Period:
Directions: Read the article "Molecule Collisions and Newton's Cradle" carefully. Use specific textual evidence and scientific concepts from the text to complete each section below.
1
Key Vocabulary in Context
Match each scientific term to its description as used in the article by writing the correct letter on the line.
1. Kinetic Energy
2. Energy Transfer
3. Collision
4. Thermal Energy
A. An event where two objects or molecules strike one another, causing energy to pass between them.
B. Heat energy; the form of energy that causes the swinging spheres in the real world to gradually slow down.
C. The energy an object or molecule possesses while it is in motion.
D. The movement of energy from one object, sphere, or molecule into another.
2
Newton's Cradle Mechanics
1. According to the text, when the first steel sphere swings down and hits the row, what happens to the spheres in the middle?
A. They swing out in alternating directions
B. They stay in place while energy moves through them
C. They compress and absorb all the kinetic energy
D. They swing upward at half the original speed
2. To what height and speed does the last sphere swing when it receives energy from the collision?
A. Much higher than the first sphere was pulled
B. Half the height and twice the speed of the first
C. Almost the same height and with the same speed
D. Exactly zero height because kinetic energy stops
3. Text-Based Explanation: Why can't the sphere next to the first sphere swing out when struck? Explain how the energy continues to travel along the row.
Cradle Collisions Worksheet Page 1 of 2 • Continue to Page 2
Physical Science • Section II
Connecting Spheres to Molecules
Student: Page 2
3
Molecular Collisions & Observable Evidence
4. According to paragraph 4, what two pieces of observable evidence prove that molecules have experienced a change in kinetic energy after a collision?
Evidence 1:
Evidence 2:
5. Compare and contrast: How is the collision between steel spheres in Newton's Cradle similar to a collision between two microscopic molecules?
4
Energy Conservation & Thermal Conversion
6. What does the article state about the total amount of energy two colliding molecules have?
A. It increases slightly during impact
B. It remains unchanged because energy is conserved
C. It drops immediately to zero
D. It converts entirely into new matter
7. Inferential Analysis: In theory, the article explains the spheres would swing back and forth forever. Why do they eventually slow down and stop in the real world? Has energy been destroyed? Support your answer with details from page C2.
5
Diagram Synthesis & Scientific Claim
Diagram Sequence Review: The article illustrates four stages: (1) Pulling the end sphere, (2) Sphere swinging down, (3) Collision impact with the adjacent sphere, and (4) The opposite end sphere swinging up and away.
8. Based on the diagram and article, write a scientific conclusion explaining why energy transfer in collisions allows energy to move through objects without permanently moving the objects in the middle.
Cradle Collisions Worksheet Page 2 of 2 • Completed Worksheet
Cradle Collisions Answer Key
Teacher Guide & Scoring Rubric
Answer Key
Molecule Collisions & Newton's Cradle
Text Reference: Amplify Science pp. C1–C2
1
Key Vocabulary Key (4 pts)
1 pt each
1. C
Kinetic Energy
The energy an object or molecule possesses while it is in motion.
2. D
Energy Transfer
The movement of energy from one object, sphere, or molecule into another.
3. A
Collision
An event where two objects or molecules strike one another, causing energy to pass between them.
4. B
Thermal Energy
Heat energy; the form of energy that causes swinging spheres to gradually slow down.
2
Newton's Cradle Mechanics Key (5 pts)
Q1–2: 1 pt each • Q3: 3 pts
Question 1: Middle Spheres Behavior Correct: B
Answer: B. They stay in place while energy moves through them.
Text Evidence (p. C1): "The two spheres on the ends keep swinging out and back, while the spheres in the middle stay in one place."
Question 2: Height and Speed of Last Sphere Correct: C
Answer: C. Almost the same height and with the same speed.
Text Evidence (p. C1): "That one swings up and away to the same height and with the same speed as the first sphere swung down..."
Question 3: Blocked Spheres & Energy Transfer Short Answer (3 pts)
Exemplar Response: The sphere next to the first one cannot swing forward because the next sphere in line is in the way and blocking it. Instead of moving, it transfers its kinetic energy to the next sphere without moving. This continues down the line until reaching the final sphere, which is not blocked by another sphere, so it swings outward.
3 pts: Explains blocking AND transfer without moving until last unblocked sphere.
2 pts: Mentions spheres are blocked but incomplete transfer chain.
1 pt: States spheres don't move without explanation.
Common Student Misconception Alert:
Students often believe the middle spheres must move or roll slightly to push each other. Emphasize the text's explicit distinction: kinetic energy travels through the matter, allowing stationary objects to transfer energy without physical displacement.
Cradle Collisions Teacher Answer Key Page 1 of 2
