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Calculate height of lift

  • Thread starter ritwik06
  • Start date
580
0
1. Homework Statement

A lift in free fall with Dr. Bhargav inside. In order to save his calculator he throws it up with 1 m/s from 1 meter above the floor of the lift. It reaches the sealing in two seconds. Calculate height of lift.



3. The Attempt at a Solution

As the wt in free fall=0.
Then distance travelled in 2 sec=2m
Total height =2+1=3m
:tongue2:
 

Answers and Replies

berkeman
Mentor
56,116
6,151
That would be my answer as well. Condolences to the Bhargav family.
 
andrevdh
Homework Helper
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The speed of the lift (and the passanger) changes as it falls downwards. This means that the speed of the calculator with respect to the lift will increase as time progresses.
 
HallsofIvy
Science Advisor
Homework Helper
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897
The speed of the lift (and the passanger) changes as it falls downwards. This means that the speed of the calculator with respect to the lift will increase as time progresses.
Not with respect to the lift. Both lift and calculator are accelerating downward at the same rate. As long as you work withing the lift, you can ignore the acceleration due to gravity. That was ritwik06's point when he said "As the wt in free fall=0".
 
andrevdh
Homework Helper
2,126
116
Well, for a while there I thought that the calculator stopped falling when it is throwed upwards (blame it on too much leave)!
 

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