Q4 of 22 Page 143

Why do millions of people turn off their lights on Earth Hour at 8:30pm (20:30 local time) on last Saturday of march every year?

Every year on this date we switch off lights on earth hour 8:30 to 9:30. This is an initiate towards saving electricity and also spreading awareness among people that resources are scarce and we need to save it.

As together being united, we can save electricity.


More from this chapter

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3

Types of coal and the percentage of carbon in each type below. Which type should be used to get high heat energy?

Lignite -25to 35 % carbon.


Bituminous 45 to 86% carbon.


Anthracite – 87 to 97% carbon

 4

Countries like Dubai, Saudi Arabia, Abu Dhabi etc. have become very rich in recent years. What could be the reason?

 4

In ‘A’ we get only ashes whereas in ‘B’ we get charcoal. Give reason.

 4

You might have read news items such as the one given below.


What are the reasons for the tragedy? List out the precautionary measures.