Question: Assume the two spheres in the picture (A is the large sphere on the left, B is the small sphere on the right) are removed. Now there are several new pairs of spheres. If each pair is placed at the original positions of A and B respectively, which pair will keep the wooden board in the same static (at-rest) state as shown?
A. Sphere A: 50 kg, Sphere B: 50 kg
B. Sphere A: 200 kg, Sphere B: 10 kg
C. Sphere A: 10 kg, Sphere B: 200 kg
D. Sphere A: 50 kg, Sphere B: 5 kg
Clues:
1. A wooden board is balanced on a purple triangular fulcrum, acting as a lever.
2. The board is horizontal, indicating it is in a state of equilibrium.
3. A large white sphere on the left side of the fulcrum is labeled "100 kg".
4. A small white sphere on the right side of the fulcrum is labeled "5 kg".
5. The 100 kg sphere is positioned very close to the fulcrum.
6. The 5 kg sphere is positioned at the far right end of the board, much farther from the fulcrum than the 100 kg sphere.
7. The wooden board has evenly spaced markings along its length.
Answer: B
Category: Physics