Most Important Selected Qs for JEE AdvancedPhysicsRotational Motion
A rod A B of mass M and length L lies on a smooth horizontal table. An impulse J is applied to end A as shown in the figure immediately after imparting the impulse:
Options
- AThe radius of curvature of trajectory of A as seen from the ground is 8 9 L .
- BThe radius of curvature of trajectory of B as seen from the ground is 2 9 L .
- CThe instantaneous axis of rotation is at a distance of L / 6 from the mid point of the rod.
- Dthe mid point of the rod will move along a straight line.
Correct answer
D. the mid point of the rod will move along a straight line.
Step-by-step solution
aligned & R = v ^2 a _ c & v = J M & = J 2 MI ^2 12 = 6 ~J ML . aligned aligned v_A & =v+ L 2 = J M + 3 J M = 4 J M a_ C_A & = ^2 L 2 = 18 J^2 M^2 L R_A & = v_A^2 a_ e A =16 J^2 M^2 M^2 L 18 J^2 = 8 9 ~L v_B & =v- L 2 = 2 J M R_B & = 4 J^2 M^2 M^2 L 18 J^2 = 2 9 L aligned