CBSE Sample Paper 2020 class 10th all Subject pdf download. C.B.S.E Class 10 Sample Paper 2020 Science, Maths, Social Science, Hindi, Sanskrit solved paper download here.
CBSE Sample Paper 2020 class 10th Subject Science
Why does the cord of an electric oven not glow while its heating element does?
Although coal and petroleum are produced by the degradation of biomass, yet we need to conserve these resources. Why?
What is atmospheric refraction? List two phenomena which can be explained on the basis of atmospheric refraction.
Name a metal of medium reactivity and write three main steps in the extraction of this metal from its sulphide ore.
List two chemical properties on the basis of which ethanol and ethanolie acid may be differentiated and explain how.
Unsaturated hydrocarbons contain multiple bonds between two carbon atoms and these compounds, which compounds are more reactive? Write a test to distinguish ethane from ethene.
C.B.S.E board Class 10th Sample Paper 2020 Section – 2
What happens to a beam of White light when it gets refracted through a glass prism? Which color deviates the most and the least after refraction through a prism? What is likely to happen if a second identical prism is placed in a inverted position with respect to the first prism? Justify your answer.
A student needs spectacles of power – 0.5 D for the correction of his vision.
- Name the defect in vision the student is suffering form.
- Find the natural and focal length of the corrective lens.
- List two cause of this defect.
Define a food chain. Design a terrestrial food chain of four tropic levels. If a pollutant enters at the producer leve, the organisms of which trophic level will have the maximum concentration of the pollutant in their bodies? What is this phenomenon called?
What are solar cells? Explain the structure of solar pannel, list two principal advantages associated with solar cells.
During the reaction of some metals with dilute hydroelectric acid, the following observations were made by a student-
- Silver does not show any change.
- Some bubbles of a gas are seen when lead is reacted with the acid.
- The reaction of sodium is found to be highly explosive.
- The temperature of the reaction mixture rises when aluminium is added to the acid
Explain these observations giving appropriate reason.
Given below are the speps for the extraction of copper from its ore. Write the chemical equation of the reactions involved in each case.
- Roasting of copper (I) sulphide
- Reduction of copper (I) oxide from copper (I) sulphide
- Electrolytic refining
How is sodium hydroxide manufactured in industries? Name the process, In this process a gas X is formed as by product. This gas reacts with lime water to give a compound Y, which is used as a bleaching agent in the chemical industry, Identify X and Y write the chemical equation of the reactions involved.
What is a homologous series of carbon compounds? Give an example and list its there characteristics.
- What is transpiration? List two functions.
- What is translocation? Why is it essential for plants?
- Where do the substances in plants reach as a result of translocation?
List in tabular form three distinguishing features between autotrophic nitration and heterotrophic nitration.
Budding, fragmentation and regeneration, all are considered as asexual model of reproduction. Why?
With the help of neat diagrams, explain the process of regeneration in planaria.
draw the pattern of magnetic field lines produced around a current caring strength conductor passing perpendicularly through a horizontal cardboard. state and apply Right Hand Thumb Rule to mark the direction of the field lines. how will the strength of the magnetic field change then the point where magnetic field is to be determined is moved away from the straigth conductor? give the reason to justify your answer
what is sexual reproduction? explain how this made of reproduction gives rise to more viable variation then Asexual reproduction. how does this affect the evolution.
why is the use of iodized salt advisable?Name the disease caused due to deficiency of iodine in our diet and state it one symptom
how do nerve impulses travel in the body? explain