How Does Surface Tension Help an Insect Escape Predators?

AI Thread Summary
The discussion centers on how a rare insect utilizes surface tension to escape predators by exuding a noxious substance that alters the surface tension around its tail. This change in surface tension leads to rapid acceleration across the water's surface, a phenomenon known as Marangoni propulsion. The surface tension of water is noted as 0.072 N m–1, with a viscosity of 10–3 Pa s. Participants seek clarification on the Marangoni Effect and its implications for the insect's escape mechanism. Understanding this effect is crucial for estimating the insect's maximum velocity and direction during its escape.
kongieieie
Messages
6
Reaction score
0
A rare species of insect about 1.5mm in diameter floats fully submerged just beneath
the surface of the water in lakes and ponds. When threatened, it responds to danger
by exuding a noxious substance from its tail that changes the surface tension on the
skin of its tail. As a result the insect accelerates, shooting quickly across the water.
Explain in detail why this occurs, and estimate the maximum velocity such an insect
would be likely to achieve, and which direction the bug accelerates. The surface
tension of water is 0.072 N m–1 and the viscosity is 10–3 Pa s.

Don't solve it or anything yet. I'll post my attempt at an answer at a later time. Just needed to post the question now.
 
Physics news on Phys.org
Okay, so I looked up a couple of books and found that this phenomenon is explained by the Marangoni propulsion. I don't really know what it means. Can someone please explain the Marangoni Effect for me please?
 
Thread 'Voltmeter readings for this circuit with switches'

Thread 'Voltmeter readings for this circuit with switches'

TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
View full post »
Thread 'Trying to understand the logic behind adding vectors with an angle between them'

Thread 'Trying to understand the logic behind adding vectors with an angle between them'

My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...
View full post »

Hot Threads

Recent Insights

Back
Top