Solution 13.2.23 from the collection Kep OE 1989

Solution 13.2.23 from the collection Kep OE 1989

On the material point of mass m = 20 kg, which moves in a horizontal line, a force of resistance R = 0,2v2. For how many seconds the point speed is reduced from 10 to 5 m / s?

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(Chapter 3 - Dynamics theme - 13.1: Defining the parameters of linear motion by the given forces) from the collection of short tasks on the theoretical mechanics Kep OE, JA Viba, OP Grapis, JA Svetinysh et al. Publishing Moscow / Graduate School / 1989, 2009, 2012.
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