Science 2003 CBSE [ All India ] Set I
To Access the full content, Please Purchase
-
Q1
Name the process by which energy is produced in a nuclear reactor. Marks:1View AnswerAnswer:
Nuclear fission -
Q2
Which one of the following groups are (a) most reactive and (b) least reactive metal? Au, Na, Cu, Ca Marks:1View AnswerAnswer:
(a) Na is the most reactive. (b) Au is the least reactive. -
Q3
The mass of a star is about 900 times that of our Sun. Explain what would happen to its core after red giant phase. Out of syllabus Marks:1View AnswerAnswer:
Out of syllabus. -
Q4
What is the special name of those days when the Sun rises exactly in the east?Out of syllabus Marks:1View AnswerAnswer:
Out of syllabus. -
Q5
What is meant by ‘persistence of vision’? Marks:1View AnswerAnswer:
Out of syllabus. -
Q6
What is the role of decomposers in our biotic environment? Marks:1View AnswerAnswer:
Decomposers decompose dead organisms to return their organic substances back into the soil so that they can be used again by the plants. -
Q7
What measures have been taken for conservation of wildlife? State any three measures. Marks:1View AnswerAnswer:
(i) Construction of National Parks (ii) Management of protected areas (iii) Construction of wild life s anctuaries. -
Q8
Which gland secretes the growth hormone? Marks:1View AnswerAnswer:
Pituitary gland. -
Q9
Name the places of our country where fields of natural gas are found. Why is it called a clean fuel? Give two reasons. Marks:2View AnswerAnswer:
India has thirty-five major fields on shore (primarily in Assam and Gujarat) and four major offshore oil fields (near Bombay, south of Pondicherry, and in the Palk Strait). Natural gas is considered as a clean fuel because of its environmentally friendly properties:
(1) commercialized natural gas is practically sulphur free and thus it produces virtually no sulphur dioxide.
(2) natural gas emits lower levels of nitrogen oxides than oil or coal and emissions of carbon dioxide are less than those of other fossil fuels. -
Q10
How are fossil fuels formed? How these fossil fuels were made? Marks:2View AnswerAnswer:
Fossil fuels are formed from the fossilized remains of dead plants and animals by exposure to heat and pressure in the Earth's crust over hundreds of millions of years.
