Find out the source of water in your region/locality. Is water from this source available to all people living in that area?
In our region or locality water sources are only available to those people or the area which are approved by the local-civic authority. The water is supplied by the government agencies at the particular timing through the taps only when we on the motors. The government agencies supplied the water from the lakes, ponds etc. to their homes directly. In the rural areas, people obtain water from the ponds, wells, streams and rivers. These water sources are used by the people for all uses like cooking food, drinking, washing clothes etc; and in urban areas, water collection occurs. In this water transport occurs through the canals, tunnels, pipelines from these sites to the water harvesting systems.
Find out about the traditional systems of water harvesting/management in your region.
Suggest some approaches towards the conservation of forests.
We saw in this chapter that there are four main stakeholders when it comes to forests and wildlife. Which among these should have the authority to decide the management of forest produce? Why do you think so?
List five things you have done over the last one week to —
(a) conserve our natural resources.
(b) increase the pressure on our natural resources.
How can you as an individual contribute or make a difference to the management of (a) forests and wildlife, (b) water resources and (c) coal and petroleum?
Why should we conserve forests and wildlife?
Compare the above system with the probable systems in hilly/mountainous areas or plains or plateau regions.
What changes can you make in your habits to become more environment-friendly?
What can you as an individual do to reduce your consumption of the various natural resources?
Why do you think that there should be equitable distribution of resources? What forces would be working against an equitable distribution of our resources?
Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
What is a good source of energy?
Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What is the difference between a reflex action and walking?
What is the importance of DNA copying in reproduction?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why should a magnesium ribbon be cleared before burning in air?
Define the principal focus of a concave mirror.
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
Which of the following pairs will give displacement reactions?
(a) NaCl solution and copper metal
(b) MgCl2 solution and aluminium metal
(c) FeSO4 solution and silver metal
(d) AgNO3 solution and copper metal.
What are alloys?
Why does the sky appear dark instead of blue to an astronaut?
Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?
Which metals do not corrode easily?
What are the limitations of extracting energy from—
(a) the wind? (b) waves? (c) tides?
Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?
What are the qualities of an ideal source of energy?
Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices.
The device used for producing electric current is called a
(a) generator.
(b) galvanometer.
(c) ammeter.
(d) motor.