Why does a hot air balloon begin to rise when heat is trapped inside of it?
Because the hot air inside is less dense than the colder air inside. This causes the air to exert an upward buoyancy force on the balloon.
It is the same reason things that are lighter than water will float.
When the air under the envelope is heated the balloon lifts. Which of the following statements is true
A hot air balloon rises because of the principle of buoyancy. Buoyancy is the upward force exerted on an object immersed in a fluid, in this case, air. When heat is trapped inside a hot air balloon, it causes the air inside the balloon to become hotter and less dense than the surrounding air. This difference in density creates an upward force that exceeds the weight of the balloon and its contents, causing it to rise.
To understand this concept further, we can break it down into a few steps:
1. First, the burner on the hot air balloon is ignited, heating the air inside the balloon envelope.
2. As the air inside the balloon heats up, it expands and becomes less dense. This is because when air is heated, its molecules gain energy and move faster, increasing the space between them.
3. The less dense hot air inside the balloon is now lighter than the cooler, denser air surrounding it.
4. According to Archimedes' principle, the upward force exerted on an object immersed in a fluid is equal to the weight of the fluid displaced by the object. In this case, the fluid is the air.
5. The hot air inside the balloon displaces a greater volume of cooler air, creating a buoyant force that pushes the balloon upward.
6. If the buoyant force exceeds the weight of the balloon and its contents, the balloon will begin to rise.
It is important to note that controlling the temperature of the air inside the balloon and managing the hot air flow are crucial for controlling the ascent or descent of the hot air balloon.