A weightless rubber balloon is filled with 200 cc of water. Its weight in water is equal to:
- A(9.8/5) N
- B(9.8/10) N
- C(9.8/2) N
- DzeroCorrect
Explanation
The correct answer is D because of Archimedes Principle. According to this principle, any object immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces.
In this specific case, the balloon is filled with 200 cc of water and is submerged in water. Since the balloon itself is weightless, the downward force is simply the weight of the 200 cc of water inside it. Simultaneously, the upward buoyant force is equal to the weight of the 200 cc of water displaced by the balloon.
Because the downward gravitational force and the upward buoyant force are equal and opposite, they cancel each other out. Therefore, the effective weight of the balloon in water is zero.

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