Gravitation – Objective Questions

Page 2 • Previous Questions with Logic & Traps


Question 8

If the distance between two masses is increased by 3 times, the gravitational force becomes:

A) 3 times B) 1/3 times C) 1/9 times D) 1/27 times

Correct Answer: C) 1/9 times

Explanation:

Gravitational force F ∝ 1/r². If r → 3r, then F → 1/(3²) = 1/9.


Question 9

A body is taken to a height equal to the radius of Earth. Its weight becomes:

A) W B) W/2 C) W/4 D) W/8

Correct Answer: C) W/4

Explanation:

At height h = R, distance from Earth’s centre = 2R. g ∝ 1/(2R)² = 1/4 → Weight = W/4.


Question 10

Which of the following quantities remains constant when a body moves from Earth to Moon?

A) Weight B) Acceleration due to gravity C) Mass D) Escape velocity

Correct Answer: C) Mass

Explanation:

Mass is independent of gravitational field. Weight, g, and escape velocity change with planet.


Question 11

At what point between Earth and Moon is the net gravitational force on a body zero?

A) Midpoint B) Near Earth C) Near Moon D) At Earth’s surface

Correct Answer: C) Near Moon

Explanation:

Earth has much greater mass than Moon, so the balance point shifts closer to the Moon.


Question 12

If mass of Earth is doubled keeping radius same, acceleration due to gravity becomes:

A) half B) double C) four times D) unchanged

Correct Answer: B) double

Explanation:

g = GM/R². If M → 2M, then g → 2g.


Question 13

A satellite moving in circular orbit has:

A) zero acceleration B) tangential acceleration only C) centripetal acceleration only D) both centripetal and tangential acceleration

Correct Answer: C) centripetal acceleration only

Explanation:

In uniform circular motion, speed is constant but direction changes, so only centripetal acceleration exists.


Question 14

The value of g decreases with height because:

A) mass of Earth decreases B) Earth’s radius increases C) distance from Earth’s centre increases D) air resistance increases

Correct Answer: C) distance from Earth’s centre increases

Explanation:

g ∝ 1/r². As distance from centre increases, g decreases.


Important Objective Tip

In gravitation problems, always visualize the distance from centre, not height from surface.


Objective Questions • Page 2 Completed

📚 IIT JEE PHYSICS – COMPLETE MASTER LIBRARY

Concepts • Problems • Tough Questions • Exam Mastery • Topper Thinking


🌍 GRAVITATION – IIT JEE EXAM MASTERY (FULL SERIES)

Concept → Board → IIT → Tough → Mastery


📘 OTHER PHYSICS LIBRARIES


🧠 THINKING & FOUNDATION


🌐 MASTER HUBS


📲 STUDENT COMMUNITY


✅ IIT JEE PHYSICS LIBRARY – COMPLETE | STRUCTURED | EXAM-ORIENTED

No comments:

Post a Comment

  📘 IIT–JEE Physics Complete Master Library (Class XI & XII) Concepts • Problems • Advanced Applications • Thinking Skill...