Given,
AB=BC=AC=l
Moment of inertia of a triangular lamina ABC
I0=kml2
DE=EF=DF=21,
AB=2l
∴ Moment of inertia of ΔDEF
IDEF=k4m(2l)2
IDEF=16kml2.
IDEF=16I0
Moment of inertia of the remaining part
Iremain=I0−16I0
=1615I0
Moment of inertia of an equilateral triangular lamina ABC, about the axis passing through its centre O and perpendicular to its plane is I_0 as shown…
JEE Main 2017 — Physics Mechanics
2017mcqhard
Moment of inertia of an equilateral triangular lamina ABC, about the axis passing through its centre O and perpendicular to its plane is I0 as shown in the figure. A cavity DEF is cut out from the lamina, where D,E,F are the mid points of the sides. Moment of inertia of the remaining part of lamina about the same axis is:
Official previous-year question
Held on 8 Apr 2017 · Verified 6 Jul 2026.
Options
- A
87I0
- B
1615I0
- C
43I0
- D
3231I0
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