Know Your World - 44


1. Which mirror is to be used to obtain a parallel beam of light from a small lamp?

Concave mirror

2. What is the Number of water molecules present in Mohr’s salt?

8

3. Which gland is responsible for the secretion of insulin?

Pancrease

4. The change in temperature of a body is 50°C. What is the change on Kelvin scale?

50 K

5. What is a good source of Vitamin ‘E’?

Fresh vegetable

6. Which are the important raw materials required in cement industry?

Limestone and clay

7. What is not the cause of low conductivity of electrolyte?

Ionization of salt

8. Epiphytes are plant which depends on other plants for which purpose?

Mechanical support

9. Cooking gas is a mixture of which gases?

Butane and propane

10. Which acid is produced when milk gets sour?

Lactic acid

11. What is Electric field intensity at a point a hollow charged spherical conductor?

Is zero

12. What is the most important requirement for the people of a flood hit area?

Inoculation against cholera

13. Which are the most commonly used chemicals in the artificial rain making or cloud seeding?

Silver Iodide (Agl)

14. Which hormone is responsible for the secretion of milk in mothers?

Lactogenic hormone

15. What happens, When water is heated from 0°C to 10°C the volume of water?

First decreases then increases

16. A vein is a vessel that carries blood which side?

Towards the heart

17. Which compound does not give a positive test in Lassaigne’s test for nitrogen?

Hydrazinc

18. What is in lichen symbiotic relationship between fungi and algae called?

Halotism

19. With which instrument can a sailor in a submarine see the objects on the surface of sea?

Periscope

20. Litmus paper used in laboratory from which obtained?

Lichen

21. Which acid is used in synthetic lemonade?

Citric acid

22. At absolute zero temperature, what will be the kinetic energy of the molecules?

Zero

23. Which is the instrument that measures air pressure?

Barometer

24. Middle ear is not found in snake. Through part do they receive sound?

Skin

25. By whom was the quantum theory first enunciated?

By Max Planck

26. Through which are the characters are transferred from parents to progeny?

DNA

27. With rise of boiling point of water, what will be the latent heat of steam?

Decreases

28. Which branch of biology deal with the study of heredity?

Genetics

29. If a proton of mass m is moving with velocity of light, how will its mass?

Unchanged

30. If we sprinkle common salt on an earthworm, why does it die?

Due to osmotic shock