|
In the given figure, a narrow beam of white light is shown to pass through a triangular glass prism. After passing through the prism it produces a spectrum XY on a screen
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3
|
6102
|
December 8, 2019
|
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With the help of a chemical equation, explain how a soda-acid fire extinguisher helps in putting out a fire
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2
|
6622
|
August 5, 2019
|
|
Why do metals not evolve hydrogen gas with nitric acid?
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2
|
1907
|
December 27, 2018
|
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Why is the red light used as a danger signal
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5
|
1351
|
December 16, 2018
|
|
How does speciation take place?
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2
|
2164
|
July 16, 2018
|
|
Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Explain
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1
|
658
|
March 22, 2018
|
|
Give any two uses of kinetic energy
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1
|
1509
|
March 21, 2018
|
|
What are the three limitations which one has to face while dealing with an infectious disease?
|
|
1
|
2962
|
March 21, 2018
|
|
What are the constituents of a balanced diet?
|
|
1
|
448
|
March 21, 2018
|
|
What are the types of food requirements of dairy animals?
|
|
1
|
3637
|
March 20, 2018
|
|
Discuss why pesticides are used in very accurate concentration and in very appropriate manner
|
|
1
|
2779
|
March 20, 2018
|
|
Differentiate between fertilisers and manures
|
|
1
|
4469
|
March 20, 2018
|
|
How is ozone layer useful to us?
|
|
1
|
1936
|
March 20, 2018
|
|
How has the method of ‘artificial selection’ by humans helped in the evolution of different vegetables?
|
|
1
|
4428
|
March 20, 2018
|
|
Explain the ways in which evolutionary relationships can be traced
|
|
1
|
3727
|
March 20, 2018
|
|
What is speciation? List four factors that could lead to speciation
|
|
1
|
9294
|
March 20, 2018
|
|
What are fossils? How are they formed?
|
|
1
|
11763
|
March 20, 2018
|
|
Explain Mendel’s experiment with peas on inheritance of characters considering only one visible contrasting character
|
|
1
|
2038
|
March 20, 2018
|
|
Describe Darwin’s theory of evolution?
|
|
1
|
8763
|
March 20, 2018
|
|
What are the various evidences in favour of evolution?
|
|
1
|
4393
|
March 20, 2018
|
|
How do Mendel’s experiments show that the traits may be dominant or recessive
|
|
1
|
2022
|
March 20, 2018
|
|
In the following crosses write the characteristics of the progeny
|
|
1
|
774
|
March 20, 2018
|
|
Mention any two points of difference between acquired and inherited traits
|
|
1
|
3937
|
March 20, 2018
|
|
Give the basic features of the mechanism of inheritance.?
|
|
1
|
1518
|
March 20, 2018
|
|
Explain with reason why giraffe has long neck
|
|
1
|
1039
|
March 20, 2018
|
|
Does geographical isolation of individuals of a species lead to formation of a new species? Provide a suitable explanation
|
|
1
|
531
|
March 20, 2018
|
|
List three factors that provide evidences in favour of evolution in organisms and state the role of each in brief
|
|
1
|
3269
|
March 20, 2018
|
|
In a cross between plants with pink flowers and plants with white flowers
|
|
1
|
849
|
March 20, 2018
|
|
Name two homologous structures in vertebrates. Why are they so called?
|
|
1
|
1585
|
March 19, 2018
|
|
“It is possible that a trait is inherited but may not be expressed.” Give a suitable example to justify this statement
|
|
1
|
9645
|
March 19, 2018
|
