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When an object is subjected to multiple forces and remains stationary, only one of the forces on the object gradually decreases to zero and then gradually increases, and the other forces remain unchanged until the object returns to the initial force situation, then the object in this process () A. The velocity of an object increases gradually from zero to a certain value B. the velocity of an object increases gradually to a certain value and then decreases gradually to zero C. the velocity of an object increases gradually from zero to a certain value and then decreases gradually to another value D
When an object is subjected to multiple forces and remains stationary, the resultant force is zero. Later, only one of the forces on the object gradually decreases to zero and then increases. Other forces remain unchanged. If the resultant force first increases and then decreases, and the direction remains unchanged, the acceleration first increases and then decreases. Since the acceleration direction and velocity direction are always the same, the velocity of the object gradually increases from zero to a certain value So a is correct, B, C and D are wrong
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