Chapter 2: Structure of Atom
Question 1.(i) Calculate the number of electrons which will together weigh one gram.(ii) Calculate the mass and charge of one mole of electrons.Answer:(i) Mass of an electron = 9.1 × 10-28 g9.1 × 10-28 g is the mass of =…
Chapter 5: Laws of Motion
Question 5. 1. Give the magnitude and direction of the net force acting on(a) a drop of rain falling down with a constant speed,(b) a cork of mass 10 g floating on water,(c) a kite skilfully held…
Class 11 Biology Chapter 1: The Living World
NCERT TEXTBOOK QUESTIONS SOLVED 1. Why are living organisms classified?Soln. Living organisms are classified because of the following reasons:(i) Easy identification.(ii)Study of organisms of other places.(iii)Study of fossils(iv)Grouping helps in study of all types of organisms while it…
Chapter 13: Magnetic Effects of Electric Current
Question 1Which of the following correctly describes the magnetic field near a long straight wire ?(i) the field consists of straight lines perpendicular to the wire(ii) the field consists of straight lines parallel to the wire(iii) the…
Chapter 7: Diversity in Living Organisms
In-Text Questions Solved NCERT Textbook for Class 9 Science – Page 80Question 1. Why do we classify organisms?Answer: For easier and convenient study we classify organisms. Question 2. Give three examples of the range of variations that you…
Chapter 1: Reproduction in Organisms
1. Why is reproduction essential for organisms?Ans: Reproduction is the ability of living organisms to produce a young one similar to itself. It ensures continuity of a species generation after generation. Reproduction introduces variation in the organisms. Useful variations…
Chapter 4: Motion in a Plane
Question 4. 1. State, for each of the following physical quantities, if it is a scalar or a vector: volume, mass, speed, acceleration, density, number of moles, velocity, angular frequency, displacement, angular velocity.Answer: Scalars: Volume, mass, speed, density, number…
Chapter 12: Electricity
Question 1A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R’, then the ratio R/R’ is :(a) 125(b) 15(c) 5(d)…
Chapter 3: Motion in a Straight Line
Question 3. 1. In which of the following examples of motion, can the body be considered approximately a point object.(a) A railway carriage moving without jerks between two stations.(b) A monkey sitting on top of a man…
