Vayudoot Aviation

1. For airborne radars wavelength generally used

40 mm

20 mm

60 mm

2. Generally the severest activity of a, heat type, TS is for

30 to 45 min

2 hrs

3 to 4 hr

3. Norwesters affect

N India

Bengal, Bihar, Orissa and Assam

Central India

4. The most hazardous cloud for variation is

CB

NS

CU

5. Over plains TS mostly occur during the

afternoon

early morning

night

6. Andhi (blinding storms) occur generally over

S India

NE India

N India

7. Norwesters normally occur during

Nights

Mornings

Afternoons

8. The diameter of Microburst is

less than 4 km

less than 6 km

less than 2 km

9. The life of Mesoscale Convective Complex TS is

6 to 24 hr

2-3 hr

3-4 hr

10. For a severe TS one of the requirements is strong Wind Shear

Slant

Horizontal

Vertical

11. Hazards of the mature stage of a TS cell include lighting, turbulence and

Icing, drizzle and microburst

WS, hail and fog

Microburst, wind-shear and anvil

Icing, microburst and WS

12. Hail is most likely to fall from a cloud

Having layers

Composed of Ice crystals

Having strong vertical development

13. The condition necessary for the formation of a thunderstorm are

Shallow lapse rate, adequate supply of moisture

Steep lapse rate, adequate supply of moisture and trigger action

Steep lapse rate, strong winds

14. Loud peals of thunder, frequent flashes of lightning, moderate or heavy showers accompanies by the light hail with maximum wind speed 15-40 kt is classified as

Light TS

Severe TS

Moderate TS

15. The trigger action may take place due to

Clear night sky, no wind

high pressure

Orographic lifting

16. Duststorm usually occurs over NW India during

Post-monsoon

Pre-Monsoon

Winter

17. Norwesters occur during

Oct-Dec

Mar-May

June-Sep

Jan-Feb

18. For detecting precipitation a Radar wavelength in the range _____ is suitable

600 - 700 mm

30 to 200 mm

400 - 500 mm

19. Severe TS cells are tilted

to the south

in vertical

to the North

20. Hail is

Frozen or partly frozen rain falling from sheet type of clouds

Solid precipitation commonly occurring over the mountainous regions in the winters

Solid precipitation falling from a deep convective cloud

21. Aircraft icing is most favoured in the cloud which have temperatures ranging between

-20°C and -40°C

below -40°C

0°C and -20°C

22. The life of a Cb cell is usually

2 -3 hr

7 to 8 hrs

3 to 4 hrs

23. Over the sea TS are more frequent

early morning

afternoon

night

24. Wind speed in Light DS is

up to 21 kt

25 kt

30 kt

25. Norwesters originates over

Deccan Plato

Khasi hills

Chota-Nagpur hills

26. Andhi (blinding storms) occur generally over

S India

N India

NE India

27. The wavelength of TS detection X band radar is

10 mm

20 mm

30 mm

28. The wavelength of storm detection S band radar is

100 mm

200 mm

50 mm

29. When flying through on active TS, lighting strikes are most likely

In the temperature band between +10° and -10°C

At or about 10000 ft

Above 5000 ft and under the anvil

In the clear air below the cloud in rain

30. A 'mature' thunderstorm has strong

updraft only

updrafts and downdrafts

downdraft only

31. Over valley and foot hills TS generally occur during

afternoon

night & early morning

32. Norwesters are

Sever thunderstorms which occur over Peninsula during hot weather period

Severe thunderstorms which occur over NE India during hot weather period

The western disturbances which affect NW India

33. Norwesters occur during

Winter

Monsoon

Post-Monsoon

Hot weather

34. A short duration, showery precipitation is associated with

AS

ST

CB

35. Hail grows by

collision with ice crystals

freezing as it leaves the cloud

up and down forces in CU cloud

collision with supercooled water drops

36. The diametre of and Macroburst

‹ 4 km

› 8 km

4 km or more

Question Bank

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