# Why do ice skaters bend at an angle when taking a turn at high speed?

1. May 20, 2010

### R Power

Why do ice skaters bend at an angle when taking a turn at high speed?
I saw some pictures of ice skaters leaning while taking turn.....in case of motorcyclists it is due to gyro effect but what in this case?

2. May 20, 2010

### mathman

It is essentially the same effect. It is necessary to counteract inertia, which would tend to keep them going straight.

3. May 20, 2010

### R Power

is there any analysis of this effect (as that of gyro there exists based on angular momentum, active reactive couple) ?
Why they would lean? Inertia would still throw them forward while turning theorotically!

4. May 20, 2010

### NeoDevin

Intertia "throws" them toward the outside of the curve.

5. May 20, 2010

### rcgldr

Leaning is done so that the outwards roll torque related to centrepital force is countered by an inwards roll torque related to gravity.

Lean angle (from vertical) Î¸ = tan-1(v2 / (g r) ).

This is unrelated to any gyroscopic effect. You could replace the wheels and tires of a bicycle with rounded skate bladed and be able to glide and steer on ice conventionally, without any gyroscopic effects.

Last edited: May 20, 2010
6. May 21, 2010

### mikeph

Force required for circular motion should be applied on the centre of mass, but for an ice skater it is applied at their base. To avoid spinning outwards they lean in. The effect of this is to move your centre of mass away from vertical with the point of contact with the floor, which provides an opposing torque (the reaction force from the floor no longer coincides with your centre of mass).

If you get the angle right you have circular motion and no net torque.

(Basically what rcgldr said but wordier).

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