Tag: some natural phenomena

Questions Related to some natural phenomena

Which of the following is an example of atmospheric electricity?

  1. Auroras

  2. Lightening

  3. Ionospheric currents

  4. All of the above


Correct Option: D
Explanation:
Examples of atmospheric electricity
(a) Auroras $\rightarrow$ appearance of streamer of reddish light in the sky, especially near northern or southern magnetic pole.
(b) Lightning
(c) Ionospheric currents

When there is lightning and 
a) You are in a jungle ,go under a tall tree.
b) You are in a jungle,go under a canopy of small trees and bushes.
c) You are out in the open,crouch on your feet,do not stand up or lie on the ground.
d) You are in an open field,stay there rather than go inside a completely covered building.Of these the good strategies are :-  

  1. B and C

  2. A and C

  3. A,B and C

  4. A,C and D


Correct Option: A
Explanation:

When there is lightning and you are in a jungle, its better to go under a canopy of small trees and bushes. The electric field is strongest near the pointed tip of an electrical conductor, and so isolated trees often make for great targets for lightning strikes. Canopy of small trees delocalises charge concentration on the other hand. 

Standing out in a field far from trees may also pose risks too as it makes you  the tallest object around and may be a target for lightning strikes. The idea will be to crouch low so that you are not the tallest object around, and at the same time keep your feet close together with your heels touching. This will help the electricity to go in one foot and out the other.

The intensity of atmospheric electric field is :

  1. same in winter as in summer

  2. lesser in winter than in summer

  3. greater in winter than in summer

  4. none of the above


Correct Option: C
Explanation:
Experiments have shown that the intensity of the electric field is greater in the middle of the day than at morning or night and is also greater in winter than in summer, which is totaly based on 'Fine weather' theory.

There are $4\times 10^{23}$ atoms in a metal sphere. If one electron is removed from 0.1% atom. what will be the charge on the sphere?

  1. $64C$

  2. $6.4C$

  3. $0.64C$

  4. $-6.4C$


Correct Option: A

Clouds get electrically charged when :

  1. The UV rays of sun falls on them

  2. Air molecules rub against water molecules

  3. Cold currents of air rub against hot currents of air

  4. Both B and C


Correct Option: D
Explanation:

The heat from the sun and warm air cause water from water bodies to vaporize. These vapour accumulate in the sky to form clouds. When these vapour molecules rub against the air molecules or other vapour molecules, they acquire charge due to friction.

Lightning occurs when an electrical charge is built up within a cloud, due to static electricity generated by supercooled water droplets colliding with ice crystals near the freezing level. When a large enough charge is built up, a large discharge will occur and can be seen as lightning. The temperature of a lightning bolt can be five times hotter than the surface of the sun. 

Both B and C are correct.
Option D 

A lightning rocket is a device used to control 

  1. time and location of a lighting strike.

  2. fuel and location of a lighting strike.

  3. the lighting of the strom

  4. none of the above


Correct Option: A
Explanation:

A lightening rocket is a rocket device, about the size of a man, that trails behind a conductor, such as fine copper wire. It is therefore, a conducting lightening rod which is grounded and positioned along side the launch tube in communication with the conductive path to thereby control time and location of a lightening strike from the thundercloud.

Which of the following statement is correct?

  1. The earth's surface is negatively charged

  2. The earth's surface is positively charged

  3. The earth's surface is neutral

  4. None of the above


Correct Option: A
Explanation:

The earth's surface is negatively charged.


Answer-(A)

Electric discharges in the atmosphere is associated with natural phenomena such as :

  1. lightning

  2. reflecting

  3. refracting

  4. none of the above


Correct Option: A
Explanation:

$Lightning$ is the natural phenomena of electric discharge through atmosphere.


Answer-(A)

Atmospheric electricity is generated due to 

  1. the accumulation of static charges

  2. the accumulation of moving charges

  3. the destruction of static charges

  4. destruction of moving charges


Correct Option: A
Explanation:

The presence of electrical action is the atmosphere, due to the accumulation of enormous static charges generated by friction of air upon itself, can be accounted for the generation of atmospheric electricity i.e, lightening and thunderstorms. 

The theory of atmospheric electricity explains which of the following phenomena?

  1. Free electricity causes thunderstorms

  2. Current due to a charge

  3. The high temperature causes people

  4. None of the above


Correct Option: A
Explanation:
Atmospheric electricity is the study of electrical charges in the Earth's atmosphere (or that of any planet). One of the phenomenons that is a result of this is that free electricity causing thunderstorm.