A uniform beam is supported at its centre by a pivot. An object with weight $40\,\text{N}$ is positioned on the beam $20\,\text{cm}$ to the left of the pivot, as illustrated. Which force and location will keep the system in balance?
- A$20\,\text{N}$ acting downwards, $40\,\text{cm}$ to the right of the pivot
- B$20\,\text{N}$ acting upwards, $40\,\text{cm}$ to the right of the pivot
- C$50\,\text{N}$ acting downwards, $10\,\text{cm}$ to the left of the pivot
- D$50\,\text{N}$ acting upwards, $10\,\text{cm}$ to the left of the pivot