The Odyssey of Flight 33 - S2-E18
Character mistake: The real speed that was reported was 3,000 knots. At one point, the plane encountered a bright flash, and violent shaking. The Captain surmised that they broke the sound barrier. 3,000 knots equates to over 3,000mph. The sound barrier (Mach 1) is about 767mph, and the captain would know that.
Character mistake: The "frozen" woman on the stairs during the welcome mayor scene repeatedly blinks her eyes.
From Agnes - With Love - S5-E20
Character mistake: Using a Texas Instruments TI-89 Titanium, the seventeenth root of 9,000,355,126,606 is 5.781163783, which means the first prime number greater is seven.
Answer: It's explained in the episode. The aliens are experimenting to see how humans react to various scenarios. This just happens to involve them using super strength.
Thanks. It's been a long time since I saw the episode so I forgot.