The mass of a lift is 2000 kg. When the tension in the supporting cable is 28000 N, then its acceleration is :

A body, under the action of a force $$\overrightarrow F = 6\widehat i - 8\widehat j + 10\widehat k,$$ acquires an accelerations of 1 m/s². The mass of this body must be

A block of mass M is attached to the lower end of a vertical spring. The spring is hung from a ceiling and has force constant value k. The mass is released from rest with the spring initially unstretched. The maximum extension produced in the length of the spring will be

An explosion blows a rock into three parts. Two parts go off at right angles to each other. These two are, 1 kg first part moving with a velocity of 12 m s^$$-$$1 and 2 kg second part moving with a velocity 8 m s^$$-$$1. If the third part flies off with a velocity of 4 m s^$$-$$1, its mass would be :