Tag: physics

Questions Related to physics

What greenhouse gas was not present in the atmosphere in pre-industrial times (before 1750)?

  1. Trichlorofluoromethane

  2. Carbon dioxide

  3. Nitrous oxide

  4. Methane


Correct Option: A
Explanation:

Trichlorofluoromethane is a type of fluorocarbon. Fluorocarbons were not present in the atmosphere before 1750. Today trichlorofluoromethane is present in the atmosphere at 242 to 244 parts per trillion (ppt).

What is the largest source of U.S. greenhouse gas emissions?

  1. Agriculture

  2. Transportation

  3. Electricity Production

  4. Home Heating


Correct Option: C
Explanation:

Electricity production accounted for 31 percent of U.S. greenhouse gas emissions in 2013, followed by transportation at 27 percent.

What can remove carbon dioxide from the atmosphere?

  1. Vegetation

  2. Oceans

  3. Carbon capture equipment

  4. All of the above


Correct Option: D
Explanation:

Vegetation and the oceans absorb somebut not all $CO _2$ emissions. Power plants can use carbon capture and sequestration technology to reduce emissions.

Which of the following is a greenhouse gas?

  1. Water vapour

  2. Methane

  3. Carbon dioxide

  4. All of the aboveĀ 


Correct Option: D
Explanation:

All the gases which has the properties that may be influenced by heat rays,has the capability to absorb infrared rays and hence act as greenhouse gases.

The green house gas is

  1. oxygen

  2. nitrogen

  3. chlorine

  4. carbon dioxide


Correct Option: D
Explanation:

The green house gas is $CO 2$.
A greenhouse gas (sometimes abbreviated GHG) is a gas in an atmosphere that absorbs<a href="http://en.wikipedia.org/wiki/Absorption
%28electromagnetic_radiation%29"> and emits radiation within the thermal infrared range. This process is the fundamental cause of the green house effect. The primary greenhouse gases in the Earth's atmophere are water vapor, $CO _2 $, $CH _4$ , nitrou oxide and Ozone.
Thus Option D is correct.

Where are HFCs most commonly used?

  1. Boats

  2. Food

  3. Refrigerators

  4. Books


Correct Option: C
Explanation:

HFCs are coolants used in air conditioners and refrigerators that have a high global warming potential of about $10,000$.

Which greenhouse gas has the highest global warming potential?

  1. Carbon dioxide

  2. Mathane

  3. Nitrous Oxide

  4. Suplhur Hexafluoride


Correct Option: D
Explanation:

This fluorinated gas absorbs the most heat over a hundred-year period. Its global warming potential is 23,500, compared to 28 for methane and 1 for carbon dioxide.

How long does methane stay in the atmosphere?

  1. $1$ month

  2. $1$ year

  3. $6$ years

  4. $12$ years


Correct Option: D
Explanation:

On average, methane lingers in the atmosphere for $12$ years, while $CO _2$ can remain for thousands of years.

Methane is a green house gas because

  1. It absorbs longer wavelengths of the electromagnetic spectrum while transmitting shorter wavelengths

  2. It absorbs shorter wavelengths of the electromagnetic spectrum while transmitting longer wavelengths

  3. It absorbs all wavelengths of the electromagnetic spectrum

  4. It transmits all wavelengths of the electromagnetic spectrum


Correct Option: A
Explanation:

Methane allows sunlight (shortwave radiation) to pass through the atmosphere freely, where it is then partially absorbed by the surface of the Earth. But some of this energy bounces back out towards space as heat. Of the heat emitted back to space, some is intercepted and absorbed by methane in the atmosphere. This molecular structure allows it to absorb some of the escaping heat and then re-emit it towards the Earth which increases global temperatures.

The greenhouse effect is caused by:

  1. Greenhouse gases in the lower atmosphere absorbing solar radiation

  2. Greenhouse gases in the lower atmosphere absorbing radiation from the Earth's surface, and preventing much of it escaping into space

  3. Too much heat in the atmosphere

  4. Too much sunshine reaching Earth


Correct Option: B
Explanation:

The greenhouse effect simply describes the fundamental role our atmosphere plays in sustaining life on Earth. Energy from the sun in the form of sunlight passes through our atmosphere and warms the surface of the Earth which then emits the energy back into the atmosphere in the form of infrared radiation. Greenhouse gases, which make up only about one per cent of the atmosphere, absorb and re-emit some of this heat, preventing much of it leaving the Earth's atmosphere. This keeps the blue planet at a comfy temperature to sustain life.
But over time, climate scientists argue, our atmosphere has accumulated more greenhouse gases, in particular carbon dioxide, methane, nitrous oxide and fluorocarbons. This increased concentration of atmospheric gases traps more heat close to the Earth's surface in the lower atmosphere and increases the average global temperature. This process, called the 'enhanced greenhouse effect', is fundamental to global warming.