The Journey of a Balloon: Understanding Volume Change Under Pressure

How does the volume of a balloon change as it rises from 20 meters to the surface?

• A. It doubles
• B. It remains the same
• C. It triples
• D. It quadruples

Answer: (C)

The volume of a balloon changes as it rises from a depth of 20 meters to the surface due to the decrease in water pressure surrounding it. According to Boyle's Law, which states that for a given mass of gas at constant temperature, the volume is inversely proportional to the pressure, as the balloon ascends, the pressure decreases. Consequently, this drop in pressure allows the gas inside the balloon to expand, increasing its volume. At a depth of 20 meters, the pressure is approximately 3 atmospheres (1 atmosphere of air pressure at the surface plus an additional 2 atmospheres from the water column). As the balloon rises to the surface where the pressure is 1 atmosphere, the reduction in pressure causes the balloon's volume to increase as it seeks to balance the internal and external pressures. In this scenario, if the volume of the balloon at 20 meters is considered, as the pressure drops significantly upon ascent, the balloon can expand to around three times its original volume, making it three times larger as it reaches the surface. This illustrates the concept that gases will expand when external pressure decreases, leading to the conclusion that the correct answer reflects the volume tripling during the ascent.

Have you ever wondered what happens to a balloon when it's submerged underwater? Let’s take a quick trip to the ocean, about 20 meters down. Here, the pressure is a lot heavier—around three times what it is at the surface. It’s all about those water columns pressing down, you know? When we start our ascent, fascinating things kick off due to this change in pressure, specifically the magic of Boyle's Law.

So, here’s the deal: Boyle’s Law tells us that the volume of a gas is inversely proportional to its pressure when the temperature is constant. As our balloon starts to float up, the pressure around it drops dramatically. From 3 atmospheres at 20 meters to just 1 atmosphere at the surface, it’s like switching from a crowded subway car to an open field.

But what does this mean for the balloon? As the pressure decreases, the gas inside the balloon opens up, or, in more technical terms, expands. Imagine how relieved the gas molecules must feel! They were cramped in there under all that pressure, and now they’re free to stretch. In fact, the volume of the balloon can increase to around three times its original size! Yes, you read that right. Talk about a growth spurt!

But why does this matter? Besides just being a cool science trick, it feeds into all sorts of practical applications, especially for divers. Understanding how volume and pressure interact can help keep divers safe. As a diver ascends, they need to manage their buoyancy carefully. Over-expanding gas can lead to unpleasant surprises—nobody wants to experience an incident called barotrauma.

Not only do balloon enthusiasts take joy in this airy phenomenon, but it creates a ripple effect in the diving community too. Whether you're using balloons for underwater research or simply having fun, keep in mind how pressure affects everything around you.

In conclusion, as this balloon rises from 20 meters to the surface, its volume indeed triples. The balloon’s journey is more than a simple ascent; it’s an excellent real-world illustration of Boyle's Law in action, transforming the way we think about gas, pressure, and even diving itself. Isn’t science just grand?