01-29-2019, 01:17 AM
Interesting question. Unfortunately, I am not that familiar with curling except for few minutes I have occasionally seen on tv.
So, you plan to attach a phone to the curling stones? I don't think that you will be able to see a difference in friction. The effect of friction would be a small acceleration, but if you consider the initial velocity and the time over which the stone decelerates to a full stop, even the "normal" deceleration (not the difference you try to find) would be lost in the noise of the sensor. Just watched a video and would estimate a shot with 1 m/s that stops after 30 s, which would mean an acceleration of 0.03 m/s². On top of this, the rotation of the stone will make it harder to interpret (although this might help to see distinguish the deceleration as an oscillation on top of the noise).
I think, it is easier to measure the rotation velocity of the stones with the gyroscope. However, I learned from another video (https://www.youtube.com/watch?v=7CUojMQgDpM), that the effect of the rotation is anything but trivial. Not sure what a good lesson could be, but maybe, your students could verify, that the sweeping reduces the amount that the stones curl. Phyphox could simply be used to verify that two shots are actually comparable as they have the rotation of both has the same angular velocity, while observing the outcome of sweeping vs. not sweeping with their own eyes.
So, you plan to attach a phone to the curling stones? I don't think that you will be able to see a difference in friction. The effect of friction would be a small acceleration, but if you consider the initial velocity and the time over which the stone decelerates to a full stop, even the "normal" deceleration (not the difference you try to find) would be lost in the noise of the sensor. Just watched a video and would estimate a shot with 1 m/s that stops after 30 s, which would mean an acceleration of 0.03 m/s². On top of this, the rotation of the stone will make it harder to interpret (although this might help to see distinguish the deceleration as an oscillation on top of the noise).
I think, it is easier to measure the rotation velocity of the stones with the gyroscope. However, I learned from another video (https://www.youtube.com/watch?v=7CUojMQgDpM), that the effect of the rotation is anything but trivial. Not sure what a good lesson could be, but maybe, your students could verify, that the sweeping reduces the amount that the stones curl. Phyphox could simply be used to verify that two shots are actually comparable as they have the rotation of both has the same angular velocity, while observing the outcome of sweeping vs. not sweeping with their own eyes.