This is another version of the demonstrations “Coin in a Glass” and “Stack of Checkers”. Stop the video at 0.29s and get the students to decide which basket will move first and also ask some to explain their reasoning. You may get conflicting ideas. Then continue with the video. Stop it again at 0.37s and get them to draw a free body force diagram of the situation. Add to it the relevant formulas. Equate the relevant formulas. Realise that the relationship is independent of mass and lo they have explained why all of the baskets start to move at the same time.