55. A soccer ball has a mass of 0.4 kg. Initially, it moves to the left at a speed of 20 m/s, but is then kicked with a speed of 30 m/s, upwards and to the right 45°. Assuming that the collision time △t = 0.01 s, which of the following values most closely approximates the magnitude of the average kick force (in Newtons)?
(A)5
(B)180
(D)1800
(C)500
(E)5000
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統計: A(0), B(1), C(2), D(2), E(0) #3239603
統計: A(0), B(1), C(2), D(2), E(0) #3239603