As shown in the figure, a and B balls with mass ma and MB are connected by light spring, a ball is suspended by string, and both balls are in a static state. If the string hanging a ball is cut off, what are the instantaneous accelerations of a and B balls at this time?

Before the string is cut, the spring force is equal to the gravity of ball B, f = MBG. At the moment of cutting, the tension of the string disappears, and the spring force remains unchanged. For B, if f-mbg = 0, then the acceleration AB = 0. For a, if MAG + F = MAAA, then AA = MAG + FMA = (MA + MB) GMA, and the direction is vertical and downward

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1. The ball with mass ma and MB is connected with light spring L1 and L2 with stiffness coefficient K as shown in the figure. When the two springs are at rest, the elongation is X1 and X2 respectively, then () A. As long as Ma = MB, there is X1 = x2b. As long as Ma > MB, there is X1 < X2C. As long as Ma < MB, there is X1 < x2d. As long as it does not exceed the elastic limit, there is always X1 > x2
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