Physics in Frozen II (minimal spoilers)

The Wind Spirit

I don't want to give too much away because you might want to see the movie, but there is a scene in which all of the characters get sucked into a tornado that is produced by the Wind Spirit, who is appropriately named Gail (play on Gale - a very strong wind). So, this made me think about Physics class and rotational motion in particular. Basically, I was wondering how the tornado works. I found the Fujita scale online that categorizes tornados and their speeds, and I figured that Disney would have chosen the tornado to be "Gale"-sized because that is what they named this spirit. This corresponds to wind speeds of about 40-72 mph. I chose 50 as an intermediate and converted it to m/s. The smaller radius for a tornado is about 300 ft and the largest is 1 mile. I chose 500 feet as a reasonable size for this smaller tornado.

50 miles / hour * 1 hour/ 3600s * 1609 m / 1 mile = 22 m/s

500 ft * 0.3048 m/1 ft = 152 m

Using the above information, I calculated the angular velocity of the tornado by V= wr and got 0.145 rad/s. 

So, when Anna, Elsa, Olaf, Kristof and Sven all get sucked into the tornado, you would think that it might slow down its rotation because they were previously at rest and now you must add their moments of inertia up, use conservation of angular momentum, and find the new angular velocity. 

But, in the movie, this happens and then everyone except Elsa gets expelled traveling radially, meaning that they are moving in their rotational path while exiting. The angular velocity of the tornado should not change in this instance because each body takes it angular velocity with it and therefore the overall momentum is conserved. However, the tornado actually speeds up after they're all ejected. This is not in accordance with conservation of momentum! Elsa then uses her ice powers or whatever it is that she is supposed to have and stops the tornado. Let's assume that the speed stays at the Gale speed of 22 m/s, or 0.145 rad/s. When she is trying to stop the motion, there is no translation. So, she needs to provide enough torque to stop the motion. She does this in about 15 seconds, so I use kinematics to find acceleration. 

Vf=Vo + at

0 m/s = 22 m/s + a (15s)

a = -1.47 m/s 

Now, I don't know if the mass of a tornado can be known, but it is interesting that Elsa can exert enough force to slow the tornado down by this much. Overall, I don't know if I can call this "bad physics" because she is supposed to be magic, but I know that it definitely piqued my interest and I highly recommend seeing the movie!