A multistorey building has 25 floors above the ground level each of height 5m. It also has 3 floors in the basement each of height 5m. A lift in building moves at a rate of 1 m/s. If a man starts from 50 m above the ground ,how long will it take him to reach at 2nd floor of basement?
Answers
Answer:20 minutes
Explanation: Total distance from 3rd floor basement to 25th floor=140 metres
starting point: 50 metres above ground (+50) = 10th floor
ending point: second floor of basement (-2)
Distance between starting point and ending point= 50 metres(above ground) + 10 metres(below ground basement) = 60 metres
speed of elevator = 1 metre per second
60 metres in floors= 60* 5 = 300 metres
Time taken to reach 5 metres or one floor = 5 seconds
to reach 300 metres = 300 seconds or 5 minutes
Answer:
60 sec
Explanation:
Each floor has the height of 5m and basement of 3 floors.
If a man starts from 50m above ground and reached at 2
nd
floor of basement.
Distance traveled above basement =50 m
And below basement =2×5=10 m
Total distance traveled=(50+10)m=60m
Rate of moving of a lift =1m/s
that is in 1 second it moves 1 metre.
So, time taken to reach 60 metre =60×1=60 s
Hence, a man reaches at 2
nd
floor of basement in 60 seconds.