A horizontal spring is compressed and a 4 kg block is placed on the left of the spring and a 7 kg block on the right. After the system is released from rest the 4 kg block slides to the left at 14 m/s and the 7 kg block slides to the right. The surface is frictionless. 33. The speed of the 7 kg block after it loses contact with the spring is

(B) Sometimes attract, sometimes repel

Explanation:

When a charged object is brought near a neutral object causes a redistribution of the charges in the second object, due to the repulsion generated by the charges of the first object. In this process, the initial net charge has not changed in the neutral object, but in some areas it is positively charged and in the others is negatively charged. Therefore, regardless of the sign of the charge of the charged object, these objects will sometimes attract and sometimes repel.