A river 3 m deep and 40 m wide is flowing at the rate of 2 km per hour. How much water will fall into the sea in a minute?
In one hour
l = 2 km = 2 x 1000 m = 2000 m b = 40 m h = 3 m
∴ Water fell into the sea in one hour = Ibh = 2000 x 40 x 3 m3
∴ Water fell into the sea in a minute
= 4000 m3
Hence, 4000 m3 of water will fall into the sea in a minute.
A small indoor greenhouse (herbarium) is made entirely of glass panes (including base) held together with tape. It is 30 cm long, 25 cm wide and 25 cm high.
(i) What is the area of the glass?
(ii) How much of tape is needed for all the 12 edges?
Parveen wanted to make a temporary shelter for her car, by making a box-like structure with tarpaulin that covers all the four sides and the top of the car (with the front face as a flap which can be rolled up). Assuming that the stitching margins are very small, and therefore negligible, how much tarpaulin would be required to make the shelter of height 2.5 m, with base dimensions 4 m × 3 m?
Mock Test Series
