NCERT solutions for Science

  NCERT solution>  Class 7 >Science  NCERT solution for class 7|| Science || Chapter 15 -Light Chapter 15 -Light  Exercise   Q1. Fill in the blanks.  a) An image that cannot be obtained on a screen is called virtual image . b) Image formed by a convex mirror is always virtual and smaller in size . c) An image formed by a plane mirror is always of the same size as that of the object. d) An image which can be obtained on a screen is called a real image.  e) An image formed by a concave lens cannot be obtained on a screen .  Q2. Make mark T the statement is true and F if it is false   a) we can obtain an enlarged and erect image by a convex mirror  b) a concave lens always form a virtual image  c) we can obtain a real enlarged and inverted image by a concave mirror . d) a real image cannot be obtained on a screen . e) a concave mirror always forms a real image   Answer-    a) false  b) true  c) tr...

  NCERT solution . > Class 7 >Science  NCERT solution for class 7 || Science || Chapter 14 -Electric current and its effect  Chapter 14 -Electric current and its effect Exercise  Q1. Draw in your notebook the symbols to represent the following components of electric circuits : connecting wires switch in the off position sell switch in the on position and battery  Answer -  Q2. Draw the circuit diagram to represent the circuit shown in figure 14 . 21. Answer -  In the above diagram the safety pin is not attached to the holding pin so the circuit is incomplete .It acts as a switch when we attached to the sefty pin to the holding pin then circuit is complete and the bulb become glow  Q3. Figure 14 .22 show found four cells fixed on a board draw lines to indicate how you will connect their terminals with wires to make a battery of four cells?   Answer -  Q4. A bulb in a circuit shown in a figure 14 . 23 does not glow can you ident...

 NCERT solution >   Class 8 > Science  NCERT solution for class 8 ||   Science ||  Chapter 18 - Pollution of air and water Chapter 18 - Pollution of air and water  Exercise  Q1. What are the different ways in which water gets contaminated ? Answer - The different ways in which water gets contaminated aur  Domestic sewage ,  Agriculture chemicals fertilizers and pesticides   Industrial waste  like chemical waste solid waste liquid waste etc Q2. At an individual level how can you help reduce air pollution ?  Answer - I do following changes in My lifestyle to reduce air pollution  Planting more and more trees around surrounding  I will not use vehicles for short distance  Use public transport as possible as  Q3. Clear transparent water is always fit for drinking comment ?  Answer - Clear transparent water does not shows any type of impurities but it may possible microorganism present...

  NCERT solution > Class 6 > Science  NCERT solution for class 6 > Science    > Chapter 16. -Garbage in Garbage out  Chapter 16. Garbage in garbage out  Q1. a)  Which kind of garbage is not converted into compost by the red worms ?  Answer -  Non biodegradable garbage like polythene bags, synthetic fibres ,glass, plastic etc are not converted into compost by red worms b) Have you seen any other organism besides red worms in your pic if yes try to find out their names draw picture of these ? Answer -   Besides than the red worms small insect bug ,spiders , centipede are also seen in compost pit and some microorganism are also present but they are not seen by naked eyes Q2. Discuss  a) Is garbage disposal the responsibility only of the government ?  Answer -   No garbage disposal is not a responsibility only of the government is the responsibility of every citizen. If  We create more garbage then it is harm...

  NCERT solution > class 6 . > Science  NCERT solution for class 6 || Science || Chapter 15 15 Air around us  Q1. What is the composition of air ?  Answer - Air is mixture of 78% of nitrogen 21% of Oxygen and 0.03% of carbon dioxide dust particles and other gases Q2. Which gas  in the atmosphere is essential for respiration ?  Answer - Oxygen gas is essential for respiration Q3. How will you prove that air supports burning  Answer -   Take a burning candle  Place it in a water filled container    Put an inverted glass on that candle  The candle blow off after sometime  And the water lavel inside the glass rises up    The components of the oxygen burns up  Show the empty place of the oxygen is occupied by water   It Prove that oxygen is necessary for burning  Q4. How will you show that air is dissolved in water ?  Answer - To show the air is dissolved in water we have to take a...