Problem P. 3926. (November 2006)
P. 3926. The two ends of a rubber string of negligible mass are fixed at the same height, such that the string is un-stretched. A small object is attached to the string in its midpoint, thus the angle of depression of the string is =30o. Then the small object is charged and vertical electric field is applied. Initially the depression angle of the string increases to 1=45o, then the electric field is changed and the depression angle increases to 2=60o. By what factor is the electric field in the second case more than that of in the first case?
Deadline expired on 11 December 2006.
|146 students sent a solution.|
|4 points:||89 students.|
|3 points:||22 students.|
|2 points:||23 students.|
|1 point:||6 students.|
|0 point:||4 students.|
|Unfair, not evaluated:||2 solutions.|