Geography
- Which meridian is used to determine world standard Time (GMT)? World Standard Time (GMT) is determined using Prime Meridian at 0° longitude. 1
- Using an atlas, tell in which of the following routes the IDL will be crossed and show them on the map. (1) Mumbai – London – New York – Los Angeles – Tokyo – IDL will be crossed. (2) Delhi – Kolkata – Singapore – Melbourne – IDL will not be cr... 1
- Why is the IDL considered with respect to the 1800 meridian only? Our 24-hour day starts at 12 midnight. Because of the earth’s rotation, the midnight occurs at different times, at different places. As the... 1
- Why doesn’t the IDL pass through land? If the IDL had passed through a land or some islands, the people there would have had to follow different dates and timings because dates wo... 1
- Why is the IDL not a straight line like the 1800 meridian? Attempt has been made to make the IDL pass through the Pacific Ocean completely. Had it passed through a land or some islands, the people th... 1
- While crossing the IDL, what changes will you make? When you cross the 180° meridian, some precautions need to be taken. There is a difference of 12 hours from Prime Meridian, if you go from E... 1
- What considerations have been made while deciding the IDL? The following points were taken into consideration while drawing the International Date Line. (IDL): 1. The direction of travel 2. The curre... 2
- The day starts in the Pacific Ocean on the earth The IDL passes through the Pacific Ocean. With reference to the IDL, the day on Earth starts in the West and ends in the East. It is one and... 1
- IDL is proving to be very useful in today’s times IDL is proving to be very useful in today’s times because: The IDL brings coordination between international airlines, transportation servic... 1
- Salinity increases in the mid-latitudinal zones. Mid-latitudinal zones lies between 25° to 35° north and south of the equator. In this zone, the rainfall is less and the supply of fresh wat... 1
- There are more salt-pans on the Western coast of India than its eastern coast. The Arabian Sea lies lying to the west and Bay of Bengal lies to the east of India. Many large peninsular rivers drain their waters in the B... 1
- With increasing depth, the temperature of sea water decreases to a certain limit. With increasing depth, the temperature of sea water decreases to a certain limit because – While most of the sunrays radiate back from the s... 1
- Oceans located at the same latitude do not have same salinity. The salinity of the oceans depends on factors like rate of evaporation and supply of fresh water. In Oceans where rate of evaporation is mor... 1
- There is higher salinity in the northern Red Sea while lower in the southern. The Red Sea is one of the saltiest bodies of water in the world, owing to high evaporation. The salinity is 36%o in the southern part becaus... 1
- Salinity is low in the land-locked Baltic Sea. The Baltic Sea lies in the temperate region. In temperate regions, the sunrays are slanting and therefore, the temperatures are lower. The s... 1
- Because of the conventional processes, convectional rainfall occurs One of the necessary conditions of convectional rainfall is intense heating of surface which causes air to expand and rise. Since land heats... 1
- We use a raincoat or umbrella to protect ourselves from rainfall. If a person is outside without any coverage, he needs to seek shelter immediately, making sure to protect his head from hailstones. 1
- Generally, it rains between June and September in our region. We get rainfall between June and September, in our region when the moisture-laden south-west monsoon winds are obstructed by the Western Gha... 1
- Why isn’t snow found in our surroundings? Because we have a moderate temperature and we are closer to the sea, snow is not found in our surroundings. 1
- Snow is found everywhere in the winters in Kashmir. Snow is found everywhere in winters of Kashmir because Kashmir is located at a higher altitude where the temperature falls below freezing po... 1
- distinguish between Snow and hail SnowHail (i)Precipitation in the form of solid particles of snow is known as snow fall.(i)Precipitation in the form of frozen water droplets... 1
- distinguish between Dew and frost DewFrost (i)When moisture-laden air near the earth’s surface comes into contact with very cold objects, condensation of vapour takes place i... 1
- What precautions should be taken while measuring rainfall? Rainfall is an important source of water on planet earth and rainfall is formed because of changes in the temperature of the air with water... 1
- If condensation occurs closer to the earth’s surface, what types of forms become visible? If condensation and solidification of the water vapour in the atmosphere closer to the earth surface are visible, they are in the form of fo... 1