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Name the venation of neem leaf and mint leaf.

Venation is the arrangement of veins in the lamina of the leaf . Two types of venation are reticulate venation and parallel venation .Both, Neem... View Article

A well of diameter 4m is dug 14m deep. The earth taken out is spread evenly all around the well to form a 40cm high embankment. Find the width of the embankment.

Given, Depth of well = 14 m, radius = 2 m. Volume of earth taken out = πr2h Let h be the height of a well and r be the radius of well... View Article

What are the advantages and disadvantages of a series combination?

If one component in a series circuit fails, then all the components in the circuit fail because the circuit has been broken. The more... View Article

Prove that diagonals of a parallelogram bisect each other

Consider a parallelogram with sides ABCD in which diagonals AC and BD bisect each other. To Prove : OA = OC and OB = OD Proof : AB || CD... View Article

A wheel of a bicycle has more than one type of motion. Explain

If a bicycle moving on a straight road,the wheel of bicycle is rotating on its axle and also moving forward in straight lines path. So, a bicycle... View Article

Use prime factorization method to find the cube root of 10648

The given number is 10648 On the prime factorisation of 10648, we get the prime factors as 10648 = 2×2×2×11×11×11 By grouping the factors in... View Article

How are nutrients replenished in the soil?

Answer: Fertile soil produces higher yields and greater plant quality. Fertile soil is rich in essential components and minerals, has good... View Article

Two poles of equal height are standing opposite to each other on either side of the road which is 80 m wide. From a point P b/w then on-road, the angle of elevation of the top of a pole is 60°and the angle of depression from the top of another pole at point P is 30°. Find the heights of the poles and distances of the point P from the poles.

Let AB and CD be the two poles of equal height standing on the two sides of the road of width 80 m. AC = 80 m Let AP = x then PC = 80 – x P is... View Article

Give two examples of periodic motion

The motion of an object which repeats at regular intervals of time is known as periodic motion . Examples are: The motion of the hands of a... View Article

In the electrolysis of water, a) name the gas collected at the anode and cathode b) why is the volume of gas collected at one electrode double than the other? c) what would happen if dilute H₂SO₄ is not added to water?

(a) In the electrolysis of water, the gas collected at cathode is hydrogen and the gas collected at anode is oxygen. (b) The gas which is... View Article

Describe the geographical conditions required for the growth of Rice.

Oryza sativa is the scientific name of rice. This is termed the paddy. The major nutrient of rice is carbohydrates. Rice is the main food crop... View Article

State Mendeleev’s periodic law. Write two achievements of Mendeleev’s periodic table.

Mendeleev's Periodic Law: 'Properties of elements are the periodic function of their atomic masses.' Achievements: (i) It could classify all the... View Article

Find the zeros of the quadratic polynomial x² + 7x + 10 and verify the relationship between the zeros and coefficients

Answer: A polynomial is an algebraic expression in which the exponent on any variable is a whole number. Polynomial’s degree is the highest or... View Article

How the presence of SO₂ detected?

SO2 is a colourless and pungent smelling gas. It can be detected with the help of potassium permanganate solution. When SO2 is passed through an... View Article

What is the no. of unpaired electrons in Mn²⁺ ion? At no. Mn = 25

Electronic configuration represents the total number of electrons that a neutral element contains. The electrons are filled according to Afbau's... View Article

What is the equivalent mass of CH3COOH?

The amount of substances that completely react with each other in the reaction is called equivalent weight. Equivalent weight is the weight of 1... View Article

Which gas is called dry ice and why?

Solid CO2 is called as dry ice , because it does not melt into liquid when heated, it changes directly into gas . This process is known as... View Article

What is the equivalent weight of NaOH?

The equivalent weight of sodium hydroxide NaOH is 40 g/mol. NaOH ⟶ Na+ +OH− Equivalent weight = Molecular weight/acidity = 40/1 = 40... View Article

An ore on treatment with dilute hydrochloric acid produces brisk effervescence to produce a colourless and odourless gas. What type of ore is this? What operation will be required to obtain metal from it?

(a) Carbonate ore: It produces CO2 with brisk effervescence. (i) Calcination: Carbonate ore is heated in limited supply of air and oxide is... View Article

What is the chemical formula of nickel bisulphate?

Nickel bisulfate - Ni(HSO4)2.6H2O. Symbol of Nickel -Ni Bisulfate - HSO4 Nickel sulfate is a highly soluble inorganic compound with the chemical... View Article

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