A balloon is released from a tall building.The total mass of the balloon including the enclosed gas is 2.0 kg.Its volume is 5.0 m³.The density of air is 1.3 kg/m³.
-Will the balloon rise,fall,or remain stationary;and why?
A)The balloon will fall because its density is greater than that of air.
B)The balloon will remain stationary because its density is less than that of air.
C)The balloon will rise because the upward buoyant force is greater than its weight.
D)The balloon will fall because the upward buoyant force is less than its weight.
E)The balloon will fall because the downward buoyant force is greater than the upward buoyant force.

Question

Quizplus · Accepted Answer

The density of the balloon is less than the density of air, so the upward buoyant force acting on the balloon is greater than its weight. Therefore, the balloon will rise. This is in accordance with Archimedes' principle, which states that an object immersed in a fluid experiences an upward force equal to the weight of the fluid displaced by the object. The volume of the balloon is 5.0 m³, so it will displace 5.0 kg of air. The weight of this displaced air is greater than the weight of the balloon, so the net force on the balloon is upward, causing it to rise.

A Balloon Is Released from a Tall Building