Q.1 Name a substance whose resistance almost remains unchanged by increase of

temperature.Q.2 Name two special characteristics of heater coil.Q.3 A wire of resistance 4ȍ is bent to form a circle. What is the resistance betweentwo diametrically opposite ends ?Q.4 How does the resistance of a conductor change if its temperature is increased?Q.5 A current of 4A flows in a wire of resistance 60ȍ.Calculate electrical energyconsumed in 2 minutes.Q.6 V-I graph for two resistors is given. Which of the two has minimum resistance?Q.7 Alloys are used in electrical heating devices rather than pure metals. Giveone reason.Q.8 An electric geyser has the ratings 2000W, 220V marked on it. What should be theminimum rating, in whole number of a fuse wire that may be required for safeuse with this geyser?Q.9 The electrical resistivity of few materials is given below in ohm-meter. Which ofthese materials can be used for making element of a heating device?A 6.84 x 10-8B 1.60 x 10-8C 1.00 x 10-4D 2.50 x 1012E 4.40 x 10-5F 2.30 x 1017Q.10 Where do we connect a fuse: with live wire or with neutral wire?Q.11 What is the resistance of an air gap?Q.12 Name two safety measures commonly used in electric circuits and appliances.Q.13 Two metallic wires A and B are connected in parallel. Wire A has length l andradius r, wire B has a length 2l and radius 2r. Compute the ratio of the total resistanceof parallel combination and the resistance of wire A.Q.14 What is the meaning of the term frequency of an alternating current? What isits value in India? Why is an alternating current considered to be advantageous overdirect current for long-range transmission of electric energy?Q.15 A TV set picture tube shoots out a beam of electrons. The current due to thisbeam is 10 mA. How many electrons will strike the TV screen every second?Q. 16 An electric wire is stretched to increase its length by 25%.By what % will theresistance be increased and what will be increase in its resistivity?Q.17 An electric iron of resistance 20ȍ takes a current of 5 A. Calculate the heatdeveloped in 30 sec.Q.18 A 60 W electric lamp gives off energy in the form of light at the rate of 7.5 J/s.What percentage of energy does the lamp transform into light?Q.19 The voltage-current variation of two metallic wires A and B at constanttemperature are shown in fig. Assuming that the wires have the same length and samediameter, explain which of the two wires will have larger resistivity.Q.20 You are given following current-time graphs from two different sources:(i) Name the type of current in two cases.(ii) Identify any one source for each type of these currents.(iii) What is the frequency of current in case II in India?Q.21 The electric power consumed by a device may be calculated by using either ofthe two expressions P = I2R or P = V 2/R . The first expression indicates that it isdirectly proportional to R whereas the second expression indicates inverseproportionality. How can the seemingly different dependence of P on R in theseexpressions be explained.Q.22. Draw a schematic diagram of a circuit containing the following electricalcomponents:(a) a resistance (b) a voltmeter (c) an electric bulb (d) a cell (e) anammeter and (f) plug keywww.zietmysore.org pdf the diagrams are here.. plzz ans them quickly i need them urgently...thx