Physicists Still Don’t Know What Puts the Curl in Curling

Re:Physicists Still Don’t Know What Puts the Curl in Curling by elif on Thursday March 15, 2018 @03:33PM (#16595871)

Except inverted. Left spin on a ball makes it go right by Magnus. Left curl makes a stone curl left.

I curl and play pool, so I've come up with reasons for the difference in my head.

The slower turning side creates more friction because it grabs the ice, the faster side glides over rather than grabbing. This is obvious when you intently watch as the curl picks up at the end of the shot.

QED, dunno why a bunch of non-curlers wrote these articles they should just curl.

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Re:Physicists Still Don’t Know What Puts the Curl in Curling by xorxarle on Thursday March 15, 2018 @07:44PM (#16597482)

An example of this could be walking on a slippery surface, your shoes grip until a threshhold is reached where you slip and increased speed seems to reduce the friction. I imagine it like tiny bumps that repel the surface of the shoe so that there is less net contact. Or is that the second hypothesis in the article? The relationship between speed and friction is discussed here, also: https://physics.stackexchange.com/questions/29561/does-frict...

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Re:Physicists Still Don’t Know What Puts the Curl in Curling by kazinator on Thursday March 15, 2018 @05:16PM (#16596589)

> The slower turning side creates more friction because it grabs the ice, the faster side glides over rather than grabbing.

For surfaces that do not melt to create a liquid film, this intuition is wrong. If any sliding is taking place, then static friction has been overcome, and kinetic friction is at play. Dry surface kinetic friction doesn't increase with speed: well, the coefficient doesn't but the actual force does!

https://physics.stackexchange.com/questions/48534/does-kinet...

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Re:Physicists Still Don’t Know What Puts the Curl in Curling by claar on Thursday March 15, 2018 @03:39PM (#16595916)

>The slower turning side creates more friction because it grabs the ice, the faster side glides over rather than grabbing.

Don't both sides turn at the same speed?

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Re:Physicists Still Don’t Know What Puts the Curl in Curling by BenjiWiebe on Thursday March 15, 2018 @03:53PM (#16596023)

Not relative to the direction of travel over the ice.

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Re:Physicists Still Don’t Know What Puts the Curl in Curling by snowwrestler on Thursday March 15, 2018 @06:42PM (#16597097)

Soccer balls also curl toward the spin. Kicking a ball to impart left spin will make the ball curl to the left in midair.

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