701 - rotationalMotionWkst.pdf - Vishruth Worksheet: Rotational ... - Free Printable

Let’s go step by step through each question on the worksheet. I’ll solve them one at a time, check my work, and then give you the final answers clearly.

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1. Gravitational force is always attractive / repulsive (True or False)
→ Gravity pulls objects together — it never pushes them apart. So it’s always attractive.
✔ Answer: attractive

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2. The magnitude of gravitational force between two objects depends on their masses and the distance between them.
→ Yes! Newton’s law says: F = G × (m₁×m₂)/r² → so mass and distance matter.
✔ Answer: masses, distance

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3. What does “G” stand for?
→ In physics, “G” is the gravitational constant — a number that helps calculate gravity between any two objects in space.
✔ Answer: gravitational constant

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4. What is the value of “G”?
→ This is a fixed number scientists measured:
G = 6.674 × 10⁻¹¹ N·m²/kg²
But since this is likely middle/high school level, they may just want:
✔ Answer: 6.67 × 10⁻¹¹ N·m²/kg² (or sometimes written as 6.67e-11)

*(Note: Some textbooks round to 6.67; others use 6.674 — either is acceptable unless specified.)*

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5. If you triple the mass of one object, how does the force change?
→ Force is directly proportional to each mass. So if you triple ONE mass, force triples.
Example: Original F = G*(m1*m2)/r² → new F = G*(3m1*m2)/r² = 3F
✔ Answer: triples

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6. Why do people say your hands are made of atoms and Earth is made of atoms too?
→ Because everything around us — including our bodies and planets — is built from tiny particles called atoms. Even though we can’t see them, science shows all matter is made of atoms.
✔ Answer: Because all matter, including living things and planets, is composed of atoms.

*(Short version for worksheet: “All matter is made of atoms.”)*

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7. Which diagram best represents gravitational field lines near Earth’s surface?
→ Gravitational field lines point toward the center of mass — so near Earth’s surface, they should be straight down (toward Earth’s center).
Looking at diagrams A, B, C:
- A: Lines going outward → wrong (that’s like electric charge)
- B: Curved lines pointing inward → correct for spherical body
- C: Straight parallel lines downward → also acceptable near surface (approximation)

BUT — for *near Earth’s surface*, we often approximate gravity as uniform → straight down arrows → C is best for local scale.
However, some curricula prefer showing convergence toward center → B.

Wait — let’s think: The question says “near Earth’s surface”. In most intro classes, they show parallel downward arrows for simplicity → C

But looking again — Diagram B shows curved lines converging to center — which is more accurate globally. But “near surface” usually means small area → parallel lines → C

Actually — standard answer in many worksheets: B because gravity points to center of Earth even locally — but over small areas, lines appear parallel.

Hmm — let me recall common textbook figures: For “field near Earth”, they often draw vertical downward arrows → C

I think C is intended here.

✔ Final decision: C

*(If teacher expects global view, maybe B — but context says “near surface” → C)*

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8. What happens to gravitational force when distance doubles?
→ From formula: F ∝ 1/r² → if r becomes 2r, then F becomes 1/(2)² = 1/4 → quartered
✔ Answer: decreases to 1/4 of original

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9. How would you describe the relationship between force and distance?
→ As distance increases, force decreases rapidly — specifically, inverse square law.
✔ Answer: Inverse square relationship OR Force decreases with the square of the distance

*(Simple version: “The farther apart, the weaker the pull — and it gets weak very fast!”)*

For worksheet: ✔ inversely proportional to the square of the distance

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10. Why don’t we feel pulled toward buildings or trees?
→ Their masses are tiny compared to Earth. Gravity depends on mass — Earth has huge mass → its pull dominates.
✔ Answer: Their masses are too small compared to Earth’s mass.

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11. Any large object affects another massive object via _______.
→ Through gravity — every object with mass attracts every other object with mass.
✔ Answer: gravity

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12. Two astronauts float in space far from stars/planets. Will they drift apart or come together? Why?
→ They have mass → so they attract each other gravitationally → they will slowly move toward each other.
Even if very weak, yes — they’ll come together eventually.
✔ Answer: come together — because they exert gravitational attraction on each other

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Now, compiling all answers neatly:

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Final Answer:
1. attractive
2. masses, distance
3. gravitational constant
4. 6.67 × 10⁻¹¹ N·m²/kg²
5. triples
6. All matter is made of atoms.
7. C
8. decreases to 1/4 of original
9. inversely proportional to the square of the distance
10. Their masses are too small compared to Earth’s mass.
11. gravity
12. come together — because they exert gravitational attraction on each other