Question

Suppose we represent the distance above the ground by a positive integer and that below the ground by a negative integer, then answer the following:
(i) An elevator descends into a mine shaft at the rate of 7metre per minute. What will be its position after one hour?
(ii) If it begins to descend from 25 m above the ground, what will be its position after 45 minutes?

Answer 1

Answer:

1) 540 metre

Step-by-step explanation:

first by unitary method we saw that 7m in 1 min so after 1hour it will be (1hour=60minutes) so 60×7=540

Answer 2

Answer:

(i) -420m

(ii) -290m

Step-by-step explanation:

(i) Given ,

Time = 60min

Speed=7m/m

Distance = S×T

= 60×7

= -420m (Below the ground)

(ii) Starting point = 25m

Rate = 7m/m

Time = 45min

Eq => Starting point - (R×T) = Final point

=> 25 -7×45

=>-290m ( Below the ground )