UPSC CDS 1 2021 English Paper

Question Numbers: 106-110In this section, you have two short passages. After each passage, you will find some items based on the passage. Read the passages and answer the items based on them. You are required to select your answers based on the content of the passage and the opinion of the author only.Noise is a common problem in both urban and rural areas, traffic noise in particular. Trees and shrubs are not only visually attractive but also can make effective noise barriers. Therefore when space permits we have to plant more trees and shrubs in areas where there is a noise problem. By doing this noise can be reduced by six decibels over a distance of 30 metres.The only thing we have to keep in mind is that the planting should be particularly dense; the trees which have dense foliage and relatively vertical orientation of arrangements should be planted. It will completely screen the source of the noise. If there is any gap in the barrier it will still allow noise to penetrate. Single-layer of trees is worthless as a noise barrier. Due to inter-reflection, multi-rows of trees are more effective. The planted trees must be taller. We can reduce the noise level by 1-5 decibels with each additional 3 feet of tree height.When the opportunity to use trees is restricted, a combination of shrubs and tall grass can be used. Instead of tarmac or gravel surfaces, soft grass ground cover is preferable. It will absorb noise rather than reflect it. Rows of trees, shrubs, crotons, ground covering plants, climbers and their flowers not only reduce noise and provide a beautiful backyard they also help block wind, provide shade, and absorb traffic pollution.