Under the action of a horizontal constant force F, an object with a mass of m on the horizontal plane starts to make a uniformly accelerated linear motion from rest. After time t, the external force is removed, and after time 2T, the object stops. What is the resistance of the object?

Uniform acceleration linear motion has: f-f = MA1 & nbsp; & nbsp; & nbsp; uniform deceleration linear motion has - F = ma2v = a1t0 = V + 2a2t from the above formula: F = F3 answer: the friction between the object and the ground is F3

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1. There is an object on a smooth horizontal plane. Under the action of horizontal constant force F, it starts to move from static state. After a certain period of time, its speed reaches V, and then after a period of time There is an object on a smooth horizontal plane, which starts to move from rest under the action of horizontal constant force F. after a certain period of time, the velocity reaches V, and then after a period of time, the velocity increases from V to 2V. In these two periods of time, what is the ratio of work done by external force F to the object?
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