Physics Worksheet

🌍 Gravitation

Chapter: Mechanics · Level ★★☆ · Time: 30 min

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NameClassDate

After this worksheet you can

Understand: Newton's Law of Universal GravitationUnderstand: The Gravitational Constant (G)Understand: Gravitational Field Strength (g)Understand: Weight vs. Mass

🧠 Section A · Concept Check ● BEGINNER 4 × 1 = 4

1Find the weight of a 90 kg person on Earth (g=9.8).

2If distance between two masses is halved, how does force change?

3A person weighs 600 N on Earth. Find their mass (g=9.8).

4Why does an astronaut's mass stay the same in orbit, even though they feel 'weightless'?

🧮 Section B · Problem Solving ● INTERMEDIATE 4 × 3 = 12

5If two masses are both doubled while distance stays the same, how does gravitational force change?

6What does the gravitational constant G represent?

7Why is gravity considered a relatively 'weak' force compared to other fundamental forces?

8A satellite orbits Earth in a circular path. What physical law explains why it doesn't fly off in a straight line?

🚀 Section C · Challenge ● CHALLENGE 2 × 2 = 4

9Find the weight of a 60 kg person on the Moon (g_moon ≈ 1.63 m/s^2).

10Why would a scale reading in a fast-descending elevator show less than your true weight?

💭 Reflection — the most useful thing I learned:

A ___/4 B ___/12 C ___/4 Total ___/20 Teacher's Signature Parent's Signature

✂ answer key — fold or cut before handing out

1 = 882 N 2 = Becomes 4 times as strong 3 = 600/9.8≈61.2 kg 4 = Mass is an intrinsic property of matter, unrelated to gravity's local strength or the sensation of weightlessness (which occurs because they're in continuous free-fall) | 5 = It becomes 4 times as strong (since F is proportional to m1*m2) 6 = A fixed proportionality constant relating mass, distance, and gravitational force strength for any two objects 7 = The gravitational constant G is extremely small, making gravity's effect negligible except when very large masses (like planets) are involved 8 = Newton's law of gravitation provides the centripetal force needed to continuously curve its path into an orbit | 9 = 60*1.63≈97.8 N 10 = The elevator's downward acceleration reduces the normal force needed to support you, which is what a scale actually measures