List of top Science Questions

Ozone gas present in upper surface of atmosphere protects earth from which radiation coming from sun?
(i) Explain with the help of labelled ray diagram, the defect of hypermetropia. How is it corrected by a lens?
(ii) A convex lens produces an inverted image magnified three times of an object placed at a distance of 15 cm from it. Calculate focal length of the lens.
Molecular formula of butanol-2 is
Which of the following is a biotic component of Ecosystem ?
What are required for photosynthesis?
'Guard Cells' are found in
Mendel crossed long and dwarf plants of pea. The percentage of long and dwarf plants in first filial generation (F\(_1\)) was
What is required for the synthesis of thyroxine hormone ?
At the time of short circuit, the electric current in the circuit becomes
O_2(g) is obtained on heating
The magnitude of magnetic force acting on a current carrying conductor in a uniform magnetic field does not depend on
Precipitation reaction is
Liquid metal at ordinary temperature is
Strong base is
The image formed by a mirror is virtual, erect and longer than the object, then the mirror will be
If the electric current passing through a fixed resistor is halved, then the heat produced in it will become
The blue colour of the sky is due to the
The refractive index of glass is 1.5. The speed of light in air is \(3 \times 10^8\) m/s. The speed of light in glass will be
The unit of power of a lens is
Write a note on the following:
(i) Gregor Johann Mendel
(ii) Reflex arc
Describe the digestive system of human with diagram.
What are the trophic levels? Give an example of a food chain and state the different trophic levels in it.
Describe co-ordination in plants with examples.
(ii) Write chemical reaction for manufacture of bleaching powder and its two applications.