An elevator car, whose floor to ceiling distance is equal to 2.7 m, starts ascending with constant acceleration of 1.2 ms?2. 2 sec after the start, a bolt begins fallings from the ceiling of the car. The free fall time of the bolt is [KCET 1994]

• A.             \[\sqrt{0.54}\,s\]         
• B.             \[\sqrt{6}\,s\]
• C.             0.7 s    
• D.              1 s