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(a) What do you do with left over food at home? (b) If you and your friends are given the choice of eating in a plastic plate or a banana leaf platter at a party, which one would you prefer and why?

Answer: (a) Leftover food can be collected and used to make compost. Compost provides nutrients essential for the growth and development of... View Article

A mass of 10 kg is at a point A on a table. It is moved to a point B. If the line joining A and B is horizontal, what is the work done on the object by the gravitational force? Explain your solution

Answer: Work is said to be done when a force applied to an object moves that object. Work done is generally referred to in relation to the force... View Article

Which of the following is not a characteristic feature of mammals? (1) Mammals have four-chambered hearts (2) They have diaphragm (3) They are not warm-blooded animals (4) They have fur on their body

Answer: (3) They are not warm-blooded animals Mammaliae are species that belong to the Mammaliae class. Mammals are one of the most advanced... View Article

Which of the following is an example of double displacement reaction? i) AgNO3 + NaCl gives AgCl + NaNO3 ii) Zn + 2HCl gives ZnCl2 + H2 iii) CH4 + 2O2 gives CO2 + 4H2O iv) H2S + Cl2 gives 2HCl + S

AgNO3 + NaCl gives AgCl + NaNO3... View Article

A copper wire has a diameter of 0.5 mm and resistivity of 1.6 × 10^-8 Ohm m. What will be the length of this wire to make its resistance 10 Ohm? How much does the resistance change if the diameter is doubled?

Resistivity (ρ) = 1.6 × 10-8 Ω m Resistance (R) = 10 Ω Diameter (d) = 0.5 mm d = 5 × 10⁻⁴ m Hence, we will get radius Radius (r) = 0.25... View Article

On increasing resistance in a circuit, current in it _____. a. increases b. decrease c. increases upto a certain point and drastically decreases d. decrease upto a certain point and then increases rapidly

On increasing resistance in a circuit, the current in it decreases. The relation between current and resistance is given by Ohm's law. Ohm's... View Article

Which of the following is not a case of physical equilibrium? i) Formation of NH4OH ii) Conversion of water into vapour iii) Conversion of water vapour onto liquid water iv) None of these

Before getting to know which among the given process is not a case of physical equilibrium let us know about physical equilibrium. The... View Article

Which of the following property is not shown by covalent compounds? a. Low boiling points and melting points b.Brittle solids c. Covalent compounds are soluble in water d.Poor conductors of heat and electricity

Covalent compounds are soluble in water... View Article

Which one of the following correctly represents a food chain? a.Grass-Grasshopper-Frog-Snake-Eagle b.Grass-Grasshopper-Eagle-Snake-Frog c. Grass-Eagle-Frog-Snake-Grasshopper d. Grass-Snake-Frog-Eagle-Grasshopper

Grass --andgt;Grasshopper --andgt; Frog --andgt; Snake --andgt; Eagle... View Article

Which of the following is a characteristic feature of ferns? a. they have male and female cone b. they have needle shaped leaves c.they have rhizoids d. their plant body is differentiated into root, stem and leaves

Their body is differentiated into root, stem and leaves. This tissue helps in the conduction of water and other substances from part of the plant... View Article

Which of the following property is not shown by covalent compounds? a. Low boiling points and melting points b. Poor Conductors of Heat and Electricity c. The movement of covalnet bond is restricted d. Brittle Solid

c. Movement of covalent molecules is restricted. The covalent molecules move about freely and tend to exist as gases or liquids or soft liquids... View Article

Which of the following conditions is not necessary for burning? a. Presence of a combustil substance b. Presence of supporter of combustion c. Heating the combustible substance to its ignition temperature d. Presence of water

There should not be any water in the surrounding.... View Article

Kirti Bookstore sold books worth Rs2,85,891 in the first week of June and books worth Rs4,00,768 in the second week of the month. How much was the sale for the two weeks together? In which week was the sale greater and by how much?

Given that The value of books sold in the first week = Rs. 2, 85,891 The value of books sold in the second week = Rs. 4, 00,768 Find out We... View Article

Take three test-tubes. Fill each of them with water. Label them A, B and C. Keep a snail in test-tube A, a water plant in test-tube B and in C, keep snail and plant both. Which test-tube would have the highest concentration of CO₂ ?

Test tube A will have the highest concentration of CO2 because the snail will take in oxygen and gives out CO2. The test tubes B contains a... View Article

Which of the following is incorrect about a heterogeneous mixture? a. Constituents of heterogeneous mixtures are uniformly mixed. b. It is composed of multiple seperate parts c. It is composed of a chemcial solution d. All of the above

Constituents of heterogeneous mixtures are uniformly mixed.... View Article

Redraw the circuit of question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure potential difference across the 12ohm resistor. What would be the readings in the ammeter and the voltmeter?

An ammeter should be connected in the circuit in series with the resistors. To measure the potential difference across the resistor it should be... View Article

Which among the following is true as per Newton’s third law: i) Action and reaction forces are always equal and opposite ii) An object tends to move in a straight line until and unless an external force is applied iii) None of the above

Action and reaction forces are always equal and opposite.... View Article

Which of the following is NOT true for solid crystals? a.Definite and characteristic heat of fusion b.Isotropic nature c.A regular periodically repeated pattern of arrangement of constituent particles in the entire crystal d.A true solid

b.Isotropic nature... View Article

Which of the following is not a characteristic of alveoli?a) They shuttle air to and from the lungs b) They maintain the shape and surface tension of the air sac c)They are arranged in clusters d)They sit at the end of the respiratory tree

Alveoli have a large surface area.... View Article

A book exhibition was held for four days in a school. The number of tickets sold at the counter on the first, second, third and final day was respectively 1094, 1812, 2050 and 2751. Find the total number of tickets sold on all the four days.

Given We are given that Number of tickets sold on the first day = 1,094 Number of tickets sold on second day= 1,812 Number of tickets sold on... View Article

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