α=Iτ
I=41mR2+mR2+41mR2+m(2R)2+12m(3R)2+m(2R)2
=(23+4+1)mR2=213mR2=213×600×102=39×104
α=39×10443×105 rad/s2=39430 rad/s2≈11 rad/s2
Two circular discs of radius each 10 cm are joined at their centres by a rod of length 30 cm and mass 600 gm as shown in figure. If the mass of each…
JEE Main 2026 — Physics Mechanics
2026mcqmedium
Two circular discs of radius each 10 cm are joined at their centres by a rod of length 30 cm and mass 600 gm as shown in figure. If the mass of each disc is 600 gm and applied torque between two discs is 43×105 dyne. cm, the angular acceleration of the discs about the given axis AB is ____ rad/s2.
Official previous-year question
Held on 28 Jan 2026 · Verified 6 Jul 2026.
Options
- A
11
- B
22
- C
100
- D
27
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