Post #1812: Bard.ai interviews for my staff AI writer position.

Bard.ai response:

Box fans are more efficient than ceiling fans because they move more air per watt of power. This is due to the design of the fan blades. Box fan blades are typically wider and have a shallower pitch than ceiling fan blades. This allows them to move more air with less effort.

In addition, box fans are typically placed closer to the people they are cooling. This means that the air they move is more concentrated, which further increases their efficiency.

However, it is important to note that ceiling fans can be more efficient in some cases. For example, ceiling fans can be more efficient than box fans in large rooms, as they can circulate the air more evenly.

Here is a table comparing the efficiency of box fans and ceiling fans:

As you can see, box fans are more efficient than ceiling fans in terms of air moved per watt. However, ceiling fans can be more efficient in terms of overall efficiency, as they can circulate the air more evenly in large rooms.

Ultimately, the best fan for you will depend on your specific needs and preferences. If you are looking for the most efficient fan, a box fan is a good option. However, if you need to cool a large room, a ceiling fan may be a better choice.

Observations

OK, both answers sucked, in their own separate ways.  And for the second answer, Bard.ai largely went down the path I laid out, even though that’s dead wrong.

Basically, instead of being factual, Bard.ai acted more like an advocate or a lawyer.  If I wanted to make the case that box fans were more efficient (even though they are not), it supplied me with the arguments it found in favor of box fans being more efficient.

Both responses conflated the definition of efficiency with an explanation for greater efficiency.  They started out simply by rephrasing what “more efficient” meant.  But both included text implying that this was the reason for the greater efficiency.  That’s weirdly … wrong.  Yes, a more efficient fan is one that moves more air for a given amount of energy input.  True.  But that in no sense explains why one fan is more efficient than another.

Both responses knew that the way to measure efficiency was something like CFM/watt, but all the numbers were bad.  None of the numbers, in either of the tables, was anything close to realistic.

And then there’s a lot of extraneous stuff, which I guess got there because, well, most discussions of fan efficiency say something like that.  Blade angle, vortex, and blowing directly at people are nonsense.  The blade size (large versus small) was on track, but never fully fleshed out.  And the gratuitous comments (“save on your heating bill”) were just out of left field.  But sound like typical ad content.

This is a clear fail.  Despite the fact that the answers are terse, and written reasonably well, the content is either unhelpful or downright wrong.  No way that Bard.ai is adequate for a technical task of this nature, given one simple prompt.

But suppose I cheat. 

Suppose I know that the answer is related to the inefficiency of pushing air rapidly, versus slowly.  Suppose I modified the prompt to point Bard.ai in the right direction?  Suppose I decided to help Bard.ai, not test Bard.ai

Try this prompt:

Explain why ceiling fans are more efficient than box fans, based on the fact that moving a large volume of air, slowly, is more efficient than moving a small volume of air, at a rapid speed.

Bard.ai gave … well, it’s still pretty much a fail.  But less so.  A more science-y sounding fail, if you will.

Sure. The principle that moving a large volume of air, slowly, is more efficient than moving a small volume of air, at a rapid speed is known as the Reynolds number. The Reynolds number is a dimensionless quantity that describes the ratio of inertial forces to viscous forces in a fluid flow. Intuitively, it means that the more air you move, the less force it takes to move it, and the more efficient the fan will be.

Ceiling fans are more efficient than box fans because they move a larger volume of air. A ceiling fan can circulate the air in an entire room, while a box fan can only cool the air around it. This means that a ceiling fan can use less power to achieve the same cooling effect as a box fan.

In addition, ceiling fans are typically designed to run at lower speeds than box fans. This is because the blades of a ceiling fan are larger than the blades of a box fan, and they can move more air at a lower speed. Running a fan at a lower speed also makes it more efficient.

For example, a 20-inch box fan uses about 73 watts of power at full speed. A 52-inch ceiling fan uses about 31 watts of power at full speed. This means that the ceiling fan is about 57% more efficient than the box fan.

Of course, the efficiency of a fan also depends on the size of the room and the amount of heat that needs to be removed. However, in general, ceiling fans are more efficient than box fans because they move a larger volume of air at a lower speed.

When you read it carefully, all I did was convince it to bullshit more convincingly.  If you read it carefully, and know something of the topic, you’ll catch the mistakes.  But it sure sounds science-y and confident.  Sometimes wrong ,but never in doubt.

The first two paragraphs are either wrong (Reynolds number) or off-point (confusing total air moved with efficiency). 

Or, at least, I’ve never seen Reynolds number used in this context.  That may just be my ignorance.  Last time I encountered it, I thought Reynolds number referred to the density of an object, relative to its air resistance.  A feather has a low Reynolds number, a bullet has a high Reynolds number.

In any case, the end of the Reynolds number explanation seems to be nonsense:   ” … the more air you move, the less force it takes to move it …”.  I read that as a violation of F=MA.  I’m not sure what the IA actually intended by it.

If you read the rest in detail, you’ll eventually realize that every paragraph has some sort of conceptual error in it.