Chapter 6: Electromagnetic Induction
6.1 Predict the direction of induced current in the situations describedby the following Figs. 6.18(a) to (f ). even if the charges are stationary [and the q (v × B) term of the Lorentzforce is not operative],…
Chapter 5: Materials Coal and Petroleum
Coal and Petroleum Class 8 Science NCERT Textbook Questions Question 1.What are the advantages of using CNG and LPG as fuels?Answer: CNG and LPG offer several benefits: Question 2.Name the petroleum product used for surfacing of roads.Answer:Bitumen…
Chapter 5: Magnetism and Matter
5.1 Answer the following questions regarding earth’s magnetism:(a) A vector needs three quantities for its specification. Name thethree independent quantities conventionally used to specify theearth’s magnetic field.(b) The angle of dip at a location in southern India…
Chapter 4: Materials Metals and Non Metals
Materials: Metals and Non-Metals Class 8 Science NCERT Textbook Questions Question 1.Which of the following can be beaten into thin sheets?(a) Zinc(b) Phosphorus(c) Sulphur(d) OxygenAnswer:(a) Zinc Question 2.Which of the following statements is correct?(a) All metals are…
Chapter 4: Moving Charges and Magnetism
4.1 A circular coil of wire consisting of 100 turns, each of radius 8.0 cmcarries a current of 0.40 A. What is the magnitude of the magneticfield B at the centre of the coil? 4.2 A long…
Chapter 3: Synthetic Fibers and Plastics
Synthetic Fibres and Plastics Class 8 Science NCERT Textbook Questions Question 1.Explain why some fibres are called synthetic.Answer:Some fibres are called synthetic fibres because they are made by man using chemicals. Question 2.Mark (✓) the correct answer.Rayon…
Chapter 3: Current Electricity
3.1 The storage battery of a car has an emf of 12 V. If the internalresistance of the battery is 0.4 Ω, what is the maximum currentthat can be drawn from the battery? 3.2 A battery of…
Chapter 2: Electrostatic Potential and Capacitance
EXERCISES 2.1 Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. Atwhat point(s) on the line joining the two charges is the electricpotential zero? Take the potential at infinity to…
Chapter 2: Microorganisms Friend and Foe
Microorganisms: Friend and Foe Class 8 Science NCERT Textbook Questions Question 1.Fill in the blanks.(a) Microorganisms can be seen with the help of a _____(b) Blue-green algae fix ______ directly from the air to enhance the fertility…
Class 12 Physics Chapter 1: Electric Charges And Fields
EXERCISES 1.1 What is the force between two small charged spheres havingcharges of 2 × 10–7C and 3 × 10–7C placed 30 cm apart in air? 1.2 The electrostatic force on a small sphere of charge 0.4…
