Question Detail

PHY 101 PHY 101 Past Questions Objective Question
Take CBT

Question

The figure shows three small spheres (A=36 kg, B=9 kg, C=4 kg) that rotate about a vertical axis. The perpendicular distance between the axis and the center of each sphere is given: A at 1 m, B at 2 m, C at 3 m. Rank the three spheres according to their rotational inertia about that axis.
Options
A C < B < A
B C = B = A
C C > B > A
Correct Answer
D C > B > A
Correct Answer

Option C is the correct answer.

Detailed Explanation

Rotational inertia I = m r². For A: I_A = 36 × 1² = 36. For B: I_B = 9 × 2² = 9 × 4 = 36. For C: I_C = 4 × 3² = 4 × 9 = 36. So all are equal. Thus C = B = A.

Hint

Compute I = mr² for each sphere.

Question Info

Course: PHY 101
Topic: PHY 101 Past Questions
Type: Objective
Difficulty: Not specified
Question 1120 of 1250
Previous Course Details Next