The diagram represents a uniform plank XY with length $4.0\,\text{m}$ and weight $300\,\text{N}$. The plank is supported by fixed supports at both ends X and Y. A child whose weight is $600\,\text{N}$ is placed at different points on the plank. At end X, the support applies an upward force $F$ on the plank. What is the value of $F$ when the child is positioned at X and when the child is positioned at Y?
- A$F = 600\,\text{N}$ when child is at X, $F = 0\,\text{N}$ when child is at Y
- B$F = 600\,\text{N}$ when child is at X, $F = 150\,\text{N}$ when child is at Y
- C$F = 750\,\text{N}$ when child is at X, $F = 0\,\text{N}$ when child is at Y
- D$F = 750\,\text{N}$ when child is at X, $F = 150\,\text{N}$ when child is at Y