Physics - Rotation Question with Solution | TestHub
A tall tower is built from alike tubes with thin walls, and from rectangular sheets whose mass is negligible compared with the tubes, as shown in the figure. The sheets are numbered from bottom as S1, S2, S3, ... . Static friction is large enough that the tubes do not slip. Each tube has radius 1 cm.
The minimum distance by which should be pulled towards right so that the tower collapses is :
Options:
Answer:
Solution:
The same argument applies whichever sheet is pulled: the tubes just below and just above the moving sheet shift by half the displacement of the sheet, the other tubes remain in place, and the centre of gravity of the system above is carried outside its base once the displacement exceeds half the margin set by the 20 cm sheet width. If the sheet is moved by a distance greater than 5 cm, the centre of gravity of the system would fall outside the base and the system collapses. Hence the minimum distance is again 5 cm, answer (D).
