A board of length rests on a single pivot at its center. A child sits at the left end. To balance, a child must sit at distance from pivot
- A
on the right
- B
on the right
- Ccheck_circle
Cannot balance
- D
on the right
Explanation
The board's CM is at the pivot, so it contributes no torque. Balance requires . But the 4-m board has only 2 m on each side of the pivot, so the 20-kg child would have to sit beyond the right end — which is physically impossible. The system cannot be balanced with the 20-kg child alone.