System of Particles and Rotational Motion - Result Question 67

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74. Moment of inertia of a uniform circular disc about a diameter is I. Its moment of inertia about an axis $\perp$ to its plane and passing through a point on its rim will be

======= ####74. Moment of inertia of a uniform circular disc about a diameter is I. Its moment of inertia about an axis $\perp$ to its plane and passing through a point on its rim will be

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/system-of-particles-and-rotational-motion/system-of-particles-and-rotational-motion—result-question-67.md (a) $5 I$

(b) $3 I$

(c) $6 I$

(d) $4 I$

[1990]

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Answer:

Correct Answer: 74. (c)

Solution:

  1. (c) M.I of uniform circular disc about its diameter $=I$

According to theorem of perpendiclar axes,

M.I. of disc about its axis $=\frac{1}{2} m r^{2}=2 I$

Applying theorem of $|$ axes, $(\because I=\frac{1}{4} m r^{2})$

M.I of disc about the given axis