A small ball is thrown vertically at the initial velocity of 21 M / s. suppose that the air resistance of the ball is 0.05 times of the gravity, then the maximum height of the ball is______ m. The speed of falling back to the throw point is_____ M / S (g = 10) m/s2). | Math enthusiast | Mathematical art

A small ball is thrown vertically at the initial velocity of 21 M / s. suppose that the air resistance of the ball is 0.05 times of the gravity, then the maximum height of the ball is__ m. The speed of falling back to the throw point is_ M / S (g = 10) m/s2).

The maximum height h = initial velocity square / 2a, a = (Mg + 0.05mg) / M = 10.5m/s2, which can be calculated by substituting the former formula
The acceleration of the highest point falling back to the throwing point is a = (mg-0.05mg) / M = 9.5m/s2, and then the displacement inference formula is used to calculate v = (root 2ah)

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