Do you want M/m value or explanation for the request?
@pushkar_2020 this is krotov problem you may see it their hint is use energy conservation
and right some equation of motion and use inequality property
Explanation of the question..how can it move when normal of the 2 spheres will balance each other out ??
One thing we should observe is the two balls looses contact with lower surface and comes in contact with outer surface after some angle, if we write the forces acting equations we can see there will be a resultant force acting in upward direction makes the tube to lift.