Tag: substances, objects and energy

Questions Related to substances, objects and energy

Choose the correct statement.

  1. Hydro and wind energy plants are non-polluting sources of energy

  2. There is infinite storage of fossil fuel inside the earth

  3. Sun can be taken as an inexhaustible source of energy

  4. Waste from a nuclear power plant can be easily disposed off


Correct Option: A,C
Explanation:

Hydro and wind energy plants are non-polluting sources of energy as they do not emit any kind of harmful substances.

Sun can be taken as an inexhaustible source of energy.

The power generated in a windmill: 

  1. is more in rainy season since damp air would mean more air mass hitting the blades

  2. can be increased by planting tall trees close to the tower

  3. depends on the height of the tower

  4. depends on wind velocity


Correct Option: D
Explanation:

Power generated in a windmill depends on the velocity of the wind. More is the velocity $\longrightarrow$ more will be the velocity of the windmills thereby generating more power.

____________ contribute to sewer gas hazards.

  1. Improper disposal of petroleum products

  2. Only gasoline

  3. Only mineral spirits

  4. None of these.


Correct Option: A
Explanation:

Sewer gases may include hydrogen sulphide, ammonia, $CO,SO _2,NO$, etc. Improper disposal of petroleum products such as gasoline and mineral gas spirits contribute to sewer gas hazards.

The residue from biogas plant serves as _______manure.

  1. inorganic

  2. organic

  3. synthetic

  4. none of these


Correct Option: B
Explanation:

Biogas is produced by anaerobic degradation of biological materials such as food wastes, animal and plant wastes. Biogas is produced when organic matter decomposes without oxygen in a process which is called anaerobic decomposition. Biogas consists mainly of methane, carbon dioxide and small amounts of impurities/residues.

So the residue from biogas plant serves as organic manure.

The nuclear reaction-
${ _{ 1 }^{ 2 }{ H } } +{ _{ 1 }^{ 2 }{ H } } _{  }\longrightarrow { _{ 2 }^{ 4 }{ He } }$ is called:

  1. fission reaction

  2. fusion reaction

  3. chain reaction

  4. thermal reaction


Correct Option: B
Explanation:

Nuclear fusion is a process where two or more nuclei combine to form an element with a higher atomic number (more protons in the nucleus). Fusion is the reverse process of nuclear fission.

The nuclear reaction -
${ _{ 1 }^{ 2 }{ H } } +{ _{ 1 }^{ 2 }{ H } } _{  }\longrightarrow { _{ 2 }^{ 4 }{ He } }$ is fusion reaction because two nuclei combine to form an element with higher atomic number.During this process, 0.7% of the mass is carried away from the system in the form of kinetic energy.
So the answer is B.

The main component of Bio gas is ___________.

  1. Methane

  2. Benzene

  3. Ethylene

  4. Ethane


Correct Option: A
Explanation:

The main component of bio gas is methane.
Methane is also the important constituent (95%) of natural gas. Methane has high heat of combustion. Hence, it is used as fuel.
$CH _4 + 2O _2 \rightarrow CO _2 + 2H _2O + heat$

Hydrogen can act as:

  1. storage medium

  2. transport medium

  3. both A and B

  4. none of above


Correct Option: C
Explanation:

Hydrogen is both a storage and transport energy medium that can connect the energy source to the energy consumer.

Why are metal pipes not an ideal means of transport for pure hydrogen?

  1. They become brittle

  2. They burst out

  3. The metals melt

  4. None of above


Correct Option: A
Explanation:

Pure hydrogen is the smallest element and some of it will inevitably escape from any known container or pipe in micro amounts. It causes the metal to become brittle, suggesting metal pipes may not be ideal for hydrogen transport.

State true or false.
Biogas is very costly and inconvenient fuel for rural areas.  
  1. True

  2. False


Correct Option: B
Explanation:
The given statement is false.
Bio-gas is an economic and convenient fuel for rural areas.

Which is not the possible solution for energy crisis?

  1. Wars and attacks

  2. Energy Simulation

  3. Perform energy audit

  4. Common stand on climate change


Correct Option: A
Explanation:

An electricity shortage is felt most acutely in heating, cooking, and water supply. Therefore, a sustained energy crisis may become a humanitarian crisis.

If an energy shortage is prolonged a crisis management phase is enforced by authorities. Energy audits may be conducted to monitor usage. Various curfews with the intention of increasing energy conservation may be initiated to reduce consumption.

Wars and attacks do not solve the problem of energy crisis, on the contrary they destroy the potential sources of energy.