What are the advantages of dam? Ans: Provide water for irrigation, generate electricity, fishiculture etc. What is Bawlis? Ans: Old method of water harvesting in Delhi What are the disadvantages of...
What is focal length? Ans: the distance between the pole and focal point. What is the relationship between the radius of curvature and focal length? Ans: R=2f What is myopia? When a person can see...