Water level in a well was 20m below ground level. During rainy season, rain water collected in different water tanks was drained nto the well and the water level rises 5 m above the previous level. The wall of the well is 1m 20 cm high and a pulley is fixed at a height of 80 cm. Raghu wants to draw water from the well. The minimum length of the rope that he can use is
(a) 17 m (b) 18 m (c) 96 m (d) 97 m

2

Answers

2016-04-08T00:16:42+05:30
As in the rainy season the water level 5 m above and the new level was 20-5=15m.
wall of the well and pulley is (1.20+.80)m= 2m.
the minimum length of the rope =(15+2)m=17m
0
2016-04-08T00:21:02+05:30
After water level rises 5 m above the previous level, water level is now (20 - 5) = 15 m below the ground level.
Height of the pulley from the ground level = 1 m 20 cm + 80 cm
                                                                   = 1.2 m + 0.8 m
                                                                   = 2 m
Therefore, the minimum length of the rope = 15 m + 2 m
                                                                    = 17 m.
Ans. (a) 17 m
1 5 1