If the resistance of an object with a mass of 2kg falling in the air is proportional to its velocity, the proportional coefficient k = 0.5N · s \, Try to find: 1, what is the final velocity of the object in the air? 2, when the velocity of the object is 20 m / s, what is the acceleration | Math enthusiast | Mathematical art

If the resistance of an object with a mass of 2kg falling in the air is proportional to its velocity, the proportional coefficient k = 0.5N · s \, Try to find: 1, what is the final velocity of the object in the air? 2, when the velocity of the object is 20 m / s, what is the acceleration

1. The object will eventually be balanced by force, so that the resistance is equal to gravity. At this time, Mg = kV, so v = 40m / s
2. When the velocity of the object is 20m / s, the object is subject to downward gravity and upward resistance. According to Newton's second law, Mg kV '= ma, a = 5m / S ^ 2
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