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.
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.
Outline a project which aims to find the dominant coat colour in dogs.
Draw the structure for the following compounds.
(i) Ethanoic acid (ii) Bromopentane*
(iii) Butanone (iv) Hexanal.
*Are structural isomers possible for bromopentane?
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?
How is the sex of the child determined in human beings?
(a) What property do all elements in the same column of the Periodic Table as boron have in common?
(b) What property do all elements in the same column of the Periodic Table as fluorine have in common?
Calculate the number of electrons constituting one coulomb of charge.
What is an homologous series? Explain with an example.
Why is variation beneficial to the species but not necessarily for the individual?
A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O – is dominant? Why or why not?
How is the concentration of hydroxide ions (OH-) affected when excess base is dissolved in a solution of sodium hydroxide?
What are the components of the transport system in human beings? What are the functions of these components?
A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains
(a) NaCl (b) HCl (c) LiCl (d) KCl
A positively-charged particle (alpha-particle) projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is
(a) towards south (b) towards east
(c) downward (d) upward
What is a balanced chemical equation? Why should chemical equations be balanced?
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?
Oil and fat containing food items are flushed with nitrogen. Why?
What is the function of an earth wire? Why is it necessary to earth metallic appliances?
How does the creation of variations in a species promote survival?
Write a balanced chemical equation with state symbols for the following reactions: