All flashcards
Flashcard 1: What is the force called that pulls objects toward Earth’s center and makes them fall?
Answer: Gravity. This invisible force attracts all objects with mass toward each other.
Flashcard 2: What is the direction of the gravitational force on an object near Earth’s surface?
Answer: Downward, toward Earth’s center. Gravity always pulls objects straight down toward Earth's core.
Flashcard 3: What is the name of the force from air that can slow a falling object?
Answer: Air resistance (drag). This friction-like force opposes motion through air.
Flashcard 4: Which statement is correct near Earth: gravity makes objects speed up downward, or slow down downward?
Answer: Gravity makes objects speed up downward. Earth's gravity accelerates all falling objects downward.
Flashcard 5: What happens to an object’s speed as it falls if air resistance is small compared with gravity?
Answer: Its speed increases (it accelerates). Gravity continuously pulls down, causing constant acceleration.
Flashcard 6: What is the term for a push or pull that can change an object’s motion?
Answer: Force. Forces cause objects to start, stop, or change direction.
Flashcard 7: Which statement is correct: mass changes on the Moon, or weight changes on the Moon?
Answer: Weight changes on the Moon. Mass stays constant, but Moon's weaker gravity reduces weight.
Flashcard 8: What is the relationship between mass and weight on Earth?
Answer: Weight depends on mass and gravity. More mass means stronger gravitational pull, creating more weight.
Flashcard 9: What evidence from everyday life shows gravity acts on objects even when you do not push them?
Answer: Dropped objects fall to the ground. This shows gravity acts constantly on all objects, not just when pushed.
Flashcard 10: Which option best explains why a crumpled paper falls faster than a flat paper: more gravity or less air resistance?
Answer: Less air resistance. Crumpling reduces surface area exposed to air, decreasing drag.
Flashcard 11: What is the best evidence-based claim when two balls of different masses are dropped together from the same height?
Answer: They hit together if air resistance is similar. Without air resistance, all objects fall at the same rate regardless of mass.
Flashcard 12: Which statement is correct: gravity is stronger closer to Earth or stronger farther from Earth?
Answer: Gravity is stronger closer to Earth. Gravitational force decreases with distance from Earth.
Flashcard 13: Which option is the best evidence that gravity is a non-contact force: it pulls without touching or only works by touching?
Answer: It pulls without touching. Objects fall without being pushed, proving gravity acts at a distance.
Flashcard 14: What is the direction of the gravitational force on a dropped object near Earth?
Answer: Downward, toward Earth’s center. Gravity always points to the center of the attracting body.
Flashcard 15: What is the term for a force from air that opposes motion through the air?
Answer: Air resistance (drag). Force from air molecules colliding with moving objects.
Flashcard 16: Which evidence best supports that gravity is always present near Earth, even indoors?
Answer: Objects fall inside buildings when released. Gravity works everywhere on Earth, not just outdoors.
Flashcard 17: Identify the correct prediction: if Earth’s gravity suddenly stopped, what would happen to a dropped ball?
Answer: It would not fall; it would keep moving based on its motion. Without gravity, objects would continue in their current motion.
Flashcard 18: Identify the correct cause: why does a tossed ball come back down after rising?
Answer: Gravity slows it upward, then pulls it downward. Gravity acts continuously, first opposing then aiding motion.
Flashcard 19: Which option is evidence that gravity is a force, not a property of falling objects?
Answer: Objects accelerate downward after being released. Acceleration shows a force is acting, not just an object property.
Flashcard 20: What is weight, in terms of gravity?
Answer: The force of gravity acting on an object. Weight measures how strongly gravity pulls on an object's mass.
Flashcard 21: What is the relationship between mass and gravity (which objects feel gravity)?
Answer: All objects with mass experience gravity. Gravity acts on everything that has mass, no exceptions.
Flashcard 22: Which statement is the best claim: why does a book fall when released?
Answer: Earth’s gravity pulls the book downward. Identifies gravity as the cause of the book's downward motion.
Flashcard 23: Which evidence best shows that gravity acts on all objects near Earth?
Answer: Different objects dropped from rest fall downward. Shows gravity affects all objects equally regardless of their properties.
Flashcard 24: What is the definition of gravity in Earth science?
Answer: A force that pulls objects toward Earth’s center. This force acts on all objects, pulling them toward Earth.
Flashcard 25: What is the name of the point that gravity pulls objects toward on Earth?
Answer: Earth’s center (center of mass). All points on Earth experience gravity toward this central point.
Flashcard 26: Which option best explains why objects do not keep moving upward after you stop pushing?
Answer: Gravity pulls downward and reduces upward speed. Gravity constantly acts downward, opposing any upward motion.
Flashcard 27: What observation supports the idea that gravity acts even when nothing touches the object?
Answer: A dropped object falls without being pushed or pulled by contact. Shows gravity is a non-contact force acting at a distance.
Flashcard 28: Which statement correctly compares gravity on Earth and the Moon?
Answer: Gravity is weaker on the Moon than on Earth. Moon's smaller mass creates less gravitational pull than Earth.
Flashcard 29: Which evidence would best support the claim that stronger gravity causes greater weight?
Answer: The same object weighs less where gravity is weaker. Shows weight depends on gravitational strength, not just mass.
Flashcard 30: What is the common classroom evidence that air resistance can change how fast objects fall?
Answer: A flat paper falls slower than a crumpled paper. Shape affects air resistance, demonstrating its effect on falling.