We agree with the statement that Only variations that confer an advantage to an individual organism will survive in a population. All the variations do not have an equal chance of surviving in the environment in which they find themselves. The chances of surviving depend on the nature of variations.Read more
We agree with the statement that Only variations that confer an advantage to an individual organism will survive in a population. All the variations do not have an equal chance of surviving in the environment in which they find themselves. The chances of surviving depend on the nature of variations. Different individual would have different kind of advantages. A bacteria that can withstand heat will survive better in a heat wave. Selection of variants by environmental factors forms the basis for revolutionary process.
The main source of water in our region (Delhi) is river Yamuna, upper Ganga canal, Bhakra storage and ground water. Water after being treated is supplied to the residents through a system of water pipes. The water is available to all the people living in the area.
The main source of water in our region (Delhi) is river Yamuna, upper Ganga canal, Bhakra storage and ground water. Water after being treated is supplied to the residents through a system of water pipes.
The water is available to all the people living in the area.
Many of us live in cities, where water is supplied by the municipal authorities. In the houses, systems of rainwater harvesting are installed which collect the water running off and channel it into a special pit created for the purpose. This helps to recharge ground water. Efforts are being made toRead more
Many of us live in cities, where water is supplied by the municipal authorities. In the houses, systems of rainwater harvesting are installed which collect the water running off and channel it into a special pit created for the purpose. This helps to recharge ground water.
Efforts are being made to collect run off rain water in soak pits. This water enriches underground water and can cause rise in water table.
Run off water from roof tops can also be collected in trenches, specially made to enrich underground water table.
(i) Recycling : The solid wastes like paper, plastics and metals, etc. are recycled. (ii) Preparation of Compost: Biodegradable domestic wastes such as left over food, fruit and vegetable peels and leaves of potted plants, etc. can be converted into compost by burying in a pit dug into ground.
(i) Recycling : The solid wastes like paper, plastics and metals, etc. are recycled.
(ii) Preparation of Compost: Biodegradable domestic wastes such as left over food, fruit and vegetable peels and leaves of potted plants, etc. can be converted into compost by burying in a pit dug into ground.
Ozone (O3) is an isotope of oxygen, i.e., it is a molecule formed by three atoms of oxygen. At the higher levels of the atmosphere, ozone performs an essential function. It shields the surface of the earth from ultraviolet (UV) radiations from the sun. These radiations are highly damaging to organisRead more
Ozone (O3) is an isotope of oxygen, i.e., it is a molecule formed by three atoms of oxygen.
At the higher levels of the atmosphere, ozone performs an essential function. It shields the surface of the earth from ultraviolet (UV) radiations from the sun. These radiations are highly damaging to organisms. Ultraviolet rays can cause skin cancer.
The advantages of nuclear energy are that : It produces a large amount of useful energy from a very small amount of a nuclear fuel (like uranium-235). Once the nuclear fuel (like uranium-235) is loaded into the reactor, the nuclear power plant can go on producing electricity for two to three years aRead more
The advantages of nuclear energy are that :
It produces a large amount of useful energy from a very small amount of a nuclear fuel (like uranium-235).
Once the nuclear fuel (like uranium-235) is loaded into the reactor, the nuclear power plant can go on producing electricity for two to three years at a stretch. There is no need for putting in nuclear fuel again and again.
It does not produce gases like carbon dioxide which contributes to greenhouse effect or sulphur dioxide which causes acid rain.
Energy stored as heat in certain regions of the earth (called hot spots) is called geothermal energy. Hot spots are the locations below earth’s crust where upward moving magma gets collected due to geological changes. When underground water comes in contact with the hot spots, steam is generated. ThRead more
Energy stored as heat in certain regions of the earth (called hot spots) is called geothermal energy. Hot spots are the locations below earth’s crust where upward moving magma gets collected due to geological changes. When underground water comes in contact with the hot spots, steam is generated. This steam is utilised to generate electricity using pipes and turbines. Sometimes hot water from the hot spot finds outlet at the surface. Such outlets are called hot springs.
The energy from the oceans can be obtained mainly in three forms. These are (i) tidal energy (ii) wave energy and (iii) ocean thermal energy There are very few sites around the world which are suitable for building tidal dams. The movement of ocean waves is associated with kinetic energy. Such sitesRead more
The energy from the oceans can be obtained mainly in three forms. These are
(i) tidal energy
(ii) wave energy and
(iii) ocean thermal energy
There are very few sites around the world which are suitable for building tidal dams.
The movement of ocean waves is associated with kinetic energy. Such sites in the world are limited where the waves strike the shore lines with sufficient power.
A concave mirror would be best suited in a solar cooker because it focuses the sunlight in a very small area of the solar cooker and a high temperature is produced in it which is sufficient to cook the food.
A concave mirror would be best suited in a solar cooker because it focuses the sunlight in a very small area of the solar cooker and a high temperature is produced in it which is sufficient to cook the food.
By saying that the refractive index of diamond is 2.42, we mean that the speed of light in diamond is lower by a factor of 2.42 relative to that in vacuum.
By saying that the refractive index of diamond is 2.42, we mean that the speed of light in diamond is lower by a factor of 2.42 relative to that in vacuum.
Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?
We agree with the statement that Only variations that confer an advantage to an individual organism will survive in a population. All the variations do not have an equal chance of surviving in the environment in which they find themselves. The chances of surviving depend on the nature of variations.Read more
We agree with the statement that Only variations that confer an advantage to an individual organism will survive in a population. All the variations do not have an equal chance of surviving in the environment in which they find themselves. The chances of surviving depend on the nature of variations. Different individual would have different kind of advantages. A bacteria that can withstand heat will survive better in a heat wave. Selection of variants by environmental factors forms the basis for revolutionary process.
See lessFind out the source of water in your region/locality. Is water from this source available to all people living in that area?
The main source of water in our region (Delhi) is river Yamuna, upper Ganga canal, Bhakra storage and ground water. Water after being treated is supplied to the residents through a system of water pipes. The water is available to all the people living in the area.
The main source of water in our region (Delhi) is river Yamuna, upper Ganga canal, Bhakra storage and ground water. Water after being treated is supplied to the residents through a system of water pipes.
See lessThe water is available to all the people living in the area.
Find out about the traditional systems of water harvesting / management in your region.
Many of us live in cities, where water is supplied by the municipal authorities. In the houses, systems of rainwater harvesting are installed which collect the water running off and channel it into a special pit created for the purpose. This helps to recharge ground water. Efforts are being made toRead more
Many of us live in cities, where water is supplied by the municipal authorities. In the houses, systems of rainwater harvesting are installed which collect the water running off and channel it into a special pit created for the purpose. This helps to recharge ground water.
Efforts are being made to collect run off rain water in soak pits. This water enriches underground water and can cause rise in water table.
Run off water from roof tops can also be collected in trenches, specially made to enrich underground water table.
See lessHow can you help in reducing the problem of waste disposal? Give any two methods.
(i) Recycling : The solid wastes like paper, plastics and metals, etc. are recycled. (ii) Preparation of Compost: Biodegradable domestic wastes such as left over food, fruit and vegetable peels and leaves of potted plants, etc. can be converted into compost by burying in a pit dug into ground.
(i) Recycling : The solid wastes like paper, plastics and metals, etc. are recycled.
See less(ii) Preparation of Compost: Biodegradable domestic wastes such as left over food, fruit and vegetable peels and leaves of potted plants, etc. can be converted into compost by burying in a pit dug into ground.
What is ozone and how does it affect any ecosystem?
Ozone (O3) is an isotope of oxygen, i.e., it is a molecule formed by three atoms of oxygen. At the higher levels of the atmosphere, ozone performs an essential function. It shields the surface of the earth from ultraviolet (UV) radiations from the sun. These radiations are highly damaging to organisRead more
Ozone (O3) is an isotope of oxygen, i.e., it is a molecule formed by three atoms of oxygen.
See lessAt the higher levels of the atmosphere, ozone performs an essential function. It shields the surface of the earth from ultraviolet (UV) radiations from the sun. These radiations are highly damaging to organisms. Ultraviolet rays can cause skin cancer.
What are the advantages of nuclear energy?
The advantages of nuclear energy are that : It produces a large amount of useful energy from a very small amount of a nuclear fuel (like uranium-235). Once the nuclear fuel (like uranium-235) is loaded into the reactor, the nuclear power plant can go on producing electricity for two to three years aRead more
The advantages of nuclear energy are that :
- It produces a large amount of useful energy from a very small amount of a nuclear fuel (like uranium-235).
- Once the nuclear fuel (like uranium-235) is loaded into the reactor, the nuclear power plant can go on producing electricity for two to three years at a stretch. There is no need for putting in nuclear fuel again and again.
- It does not produce gases like carbon dioxide which contributes to greenhouse effect or sulphur dioxide which causes acid rain.
See lessWhat is geothermal energy?
Energy stored as heat in certain regions of the earth (called hot spots) is called geothermal energy. Hot spots are the locations below earth’s crust where upward moving magma gets collected due to geological changes. When underground water comes in contact with the hot spots, steam is generated. ThRead more
Energy stored as heat in certain regions of the earth (called hot spots) is called geothermal energy. Hot spots are the locations below earth’s crust where upward moving magma gets collected due to geological changes. When underground water comes in contact with the hot spots, steam is generated. This steam is utilised to generate electricity using pipes and turbines. Sometimes hot water from the hot spot finds outlet at the surface. Such outlets are called hot springs.
See lessWhat are the limitations of the energy that can be obtained from the oceans?
The energy from the oceans can be obtained mainly in three forms. These are (i) tidal energy (ii) wave energy and (iii) ocean thermal energy There are very few sites around the world which are suitable for building tidal dams. The movement of ocean waves is associated with kinetic energy. Such sitesRead more
The energy from the oceans can be obtained mainly in three forms. These are
(i) tidal energy
(ii) wave energy and
(iii) ocean thermal energy
There are very few sites around the world which are suitable for building tidal dams.
The movement of ocean waves is associated with kinetic energy. Such sites in the world are limited where the waves strike the shore lines with sufficient power.
See lessWhat kind of mirror – concave, convex or plain – would be best suited for use in a solar cooker? Why?
A concave mirror would be best suited in a solar cooker because it focuses the sunlight in a very small area of the solar cooker and a high temperature is produced in it which is sufficient to cook the food.
A concave mirror would be best suited in a solar cooker because it focuses the sunlight in a very small area of the solar cooker and a high temperature is produced in it which is sufficient to cook the food.
See lessThe refractive index of diamond is 2.42. What is the meaning of this statement?
By saying that the refractive index of diamond is 2.42, we mean that the speed of light in diamond is lower by a factor of 2.42 relative to that in vacuum.
By saying that the refractive index of diamond is 2.42, we mean that the speed of light in diamond is lower by a factor of 2.42 relative to that in vacuum.
See less