CBSE | NCERT CLASS

  1 . define good conductor of electricity? Give example. Answer: the materials which allow electric current to pass through them easily are called good conductors of electricity or simply conductors of electricity.  Example:  generally metals are good conductor of electricity such as copper aluminium etc.  2.   define bad contactor of electricity. Give example.  Answer:  the materials which do not allow electric current to pass through them easily are called bad conductor of electricity.  Example:  the materials such as rubber plastic and wood are example of bad conductor of electricity.  3. Name some liquids which can conduct electricity.  Answer: solution of acid,  solution of base, salt in water.  A solution of of sulphuric acid,  hydrochloric acid,  aur any other acid in water conducts electricity.  A solution of sodium hydroxide, potassium Hydroxide or any other soluble base in water conduct electricity. A solution of copper sulphate, common salt or any other salt in water also

Hydrocarbons A compound made up of hydrogen and carbon only is called hydrocarbon (hydrogen   +   carbon = hydrocarbon ). Example of hydrocarbons are Methane (CH4), Ethane (C2H6), Ethene (C2H4), ethyne (C2H2).

Definition: the periodic table is a chart of elements prepared in such a way that the elements having similar properties of occur in the same vertical column or group. The horizontal rows of periodic table called periods. The vertical columns of the periodic table called groups.

Definition of Dobereiner's theory law in English and Hindi When elements are arranged in the order of increasing atomic masses, groups of 3 elements (known as triads), having similar properties are obtained. The atomic mass of the middle element of the triad being equal to the Arithmetic mean of the atomic masses of the other two elements.

In NCERT solution for class 8 of science chapter 13 Sound get questions with answers, worksheet, notes etc. Question 1: Choose the correct answer: Sound can travel through (a) gases only (b) solids only (c) liquids only (d) solids, liquids and gases. Answer 1: Sound can travel through (d) solids, liquids and gases.

In NCERT Solution of Class 8 of math chapter 7 Cube and Cube Roots get worksheet, questions answers,solve paper. Question 1: Which of the following numbers are not perfect cubes: (i) 216 (ii) 128 (iii) 1000 (iv) 100 (v) 46656

In NCERT solution for math for Set of class 11 chapter 1 get NCERT and CBSE questions,set worksheet,solve answers. Chapter 1 (Set) Exercise: 1.1 Question 1: Which of the following are sets? Justify your answer. (i) The collection of all months of a year beginning with the letter J. (ii) The collection of ten most talented writers of India. (iii) A team of eleven best-cricket batsmen of the world.