131 + Interview Questions in HEATING-AND-CHEMICAL-EFFECT-OF-CURRENT IN GENERAL AWARENESS Page 1 InterviewSolution

1.	For a thermocouple, the neutral temperature is `270^(@)C` and the temperature of its cold junction is `20^(@)C` . If there is no deflection in the galvanometer, the temperature of the hot junction should beA. `210^(@)C`B. `540^(@)C`C. `520^(@)C`D. `209^(@)C`
Answer» Correct Answer - C

Discussion

2.	The neutral temperature of a thermocouple is `350^(@)C` when the cold junction is at . `0^(@)C` When the cold junction is immersed in a bath of `30^(@)C`, the inversion temperature isA. `700^(@)C`B. `600^(@)C`C. `35^(@)C`D. `670^(@)C`
Answer» Correct Answer - D

Discussion

3.	For a thermocouple the neutral temperature is `270^(@)C` when its cold junction is at `20^(@)C` . What will be the neutral temperature and the temperature of inversion when the temperature of cold junction is increased to `40^(@)C`A. `290^(@)C, 580^(@)C`B. `270^(@)C, 580^(@)C`C. `270^(@)C, 500^(@)C`D. `290^(@)C, 540^(@)C`
Answer» Correct Answer - C

Discussion

4.	A thermoelectric refrigerator works onA. Joule effectB. Seeback effectC. Peltier effectD. Thermonic emission
Answer» Correct Answer - C

Discussion

5.	Consider the following statements regarding a thermocouple. (A) The neutral temperature does not depend on the temperature of the cold junction. (B) The inversion temperature does not depend on the temperature of the cold junction.A. IncreasesB. Approaches inversion temperatureC. DecreasesD. Remains the same
Answer» Correct Answer - D

Discussion

6.	If a high power heater is connected to electric mains, then the bulbs in the house become dim, because there is aA. Current dropB. Potential dropC. No current dropD. No potential drop
Answer» Correct Answer - B

Discussion

7.	Two bulbs, one of 50 watt and another of 25 watt are connected in series to the mains. The ratio of the currents through them isA. `2 : 1`B. `1 : 2`C. `1 : 1`D. Without voltage, cannot be calculated
Answer» Correct Answer - C

Discussion

8.	4 bulbs marked 40 W , 250 V are connected in series with 250 V mains. The total power isA. 10 WB. 40 WC. 320 WD. 160 W
Answer» Correct Answer - A

Discussion

9.	The current flowing through a lamp marked as 50 W and 250 V isA. 5 ampB. `2.5 amp`C. 2 ampD. `0.2 amp`
Answer» Correct Answer - D

Discussion

10.	An electric lamp is marked 60 W , 230 V . The cost of a 1 kWh of energy is Rs . 1.25. The cost of using this lamp 8 hrs a day for 30 day isA. Rs. 10B. Rs. 16C. Rs. 18D. Rs. 20
Answer» Correct Answer - C

Discussion

11.	Two electic bulbs rated `P_(1)` watt `V` volts and `P_(2)` watt `V` volts are connected in parallel and `V` volts are applied to it. The total power will beA. `P_(1)+P_(2)` wattB. `sqrt(P_(1)P_(2))` wattC. `(P_(1)P_(2))/(P_(1)+P_(2))` wattD. `(P_(1)+P_(2))/(P_(1)P_(2))` watt
Answer» Correct Answer - A

Discussion

12.	A 100 W bulb `B_(1)` and two 60 W bulbs `B_(2)` and `B_(3)`, are connected to a 250V source, as shown in the figure now `W_(1),W_(2)` and `W_(3)` are the output powers of the bulbs `B_(1),B_(2)` and `B_(3)` respectively thenA. `W_(1)gt W_(2)=W_(3)`B. `W_(1)gt W_(2)gt W_(3)`C. `W_(1)lt W_(2)=W_(3)`D. `W_(1)lt W_(2)lt W_(3)`
Answer» Correct Answer - D

Discussion

13.	Two electric bulbs A and B are rated as 60 W and 100 W . They are connected in parallel to the same source. Then,A. Both draw the same currentB. A draws more current than BC. B draws more current than AD. Current drawn are in the ratio of their resistances
Answer» Correct Answer - C

Discussion

14.	A bulb has specification of one kilowatt and 250 volts , the resistance of bulb isA. `125 Omega`B. `62.5 Omega`C. `0.25 Omega`D. `625 Omega`
Answer» Correct Answer - B

Discussion

15.	If in a voltaic cell 5 gm of zinc is consumed, then we get how many ampere hours ? (Given that E.C.E. of Zn is `3.387xx10^(-7)` kg/coulomb)A. `2.05`B. `8.2`C. `4.1`D. `5xx3.387xx10^(-7)`
Answer» Correct Answer - C

Discussion

16.	If `2.2` kilowatt power is transmitted through a 10 ohm line at 22000 volt , the power loss in the form of heat will beA. `0.1` wattB. 1 wattC. 10 wattD. 100 watt
Answer» Correct Answer - A

Discussion

17.	If a 2 kW boiler is used everyday for 1 hour, then electrical energy consumed by boiler in thirty days isA. 15 unitB. 60 unitC. 120 unitD. 240 unit
Answer» Correct Answer - B

Discussion

18.	If `2.2` kW power is transmitted through a `100 Omega` line at , 000,22 V the power loss in the form of heat will beA. `0.1 W`B. 1 WC. 10 WD. 100 W
Answer» Correct Answer - B

Discussion

19.	If for a thermocouple `T_(n))` is the neutral temperature, `T_(c )` is the tempreture of the cold junction and `T_(i))` is the temperature of inversion, thenA. `T_(i)=2T_(n)-T_(c )`B. `T_(n)=T_(i)-2T_(c )`C. `T_(i)=T_(n)-T_(c )`D. None of these
Answer» Correct Answer - A

Discussion

20.	The cold junction of a thermocouple is maintained at `10^(@)C` . No thermo e.m.f . is developed when the hot junction is maintained at `530^(@)C` . The neutral temperature isA. `260^(@)C`B. `270^(@)C`C. `265^(@)C`D. `520^(@)C`
Answer» Correct Answer - B

Discussion

21.	An electric bulb of 100 watt is connected to a supply of electricity of 220 V . Resistance of the filament isA. `484 Omega`B. `100 Omega`C. `22000 Omega`D. `242 Omega`
Answer» Correct Answer - A

Discussion

22.	Who among the following scientists made the statement –"Chemical change can produce electricity"A. GalvaniB. FaradayC. CoulombD. Thomson
Answer» Correct Answer - A

Discussion

23.	Peltier co-efficient of a thermo couple is 2 nano volts. How much heat is developed at a junction if 2.5 amp current flows for 2 minuteA. 6 ergsB. `6xx10^(-7)` ergsC. 16 ergsD. `6xx10^(-3)` erg
Answer» Correct Answer - A

Discussion

24.	Peltier coefficient for the junction of a pair of metals is proportional toA. T absolute temperature of the junctionB. Square of absolute temperature of the junctionC. `(1)/("Absolute temperature of the junction")`D. `(1)/("Square of absolute temperature of the junction")`
Answer» Correct Answer - A

Discussion

25.	The electrochemical equivalent Z of any element can be obtained by multiplying the electrochemical equivalent of hydrogen withA. Atomic weightB. Molecular weightC. Chemical equivalentD. A constant
Answer» Correct Answer - C

Discussion

26.	The relation between faraday constant F , electron charge e and avogadro number N isA. F = N/eB. F = NeC. `N=F^(2)`D. `F = N^(2)e`
Answer» Correct Answer - B

Discussion

27.	The electrochemical equivalent of a material depends onA. The nature of the materialB. The current through the electrolyteC. The amount of charge passed through electrolyteD. The amount of material present in electrolyte
Answer» Correct Answer - A

Discussion

28.	The relation between faraday constant `(F)`, chemical equicalent `(E)` and electrochemical equivalent `(Z)` isA. `F = EZ`B. `F=(Z)/(E )`C. `F=(E )/(Z)`D. `F=(E )/(Z^(2))`
Answer» Correct Answer - C

Discussion

29.	Faraday’s 2nd law states that mass deposited on the electrode is directly proportional toA. Atomic massB. Atomic mass × VelocityC. Atomic mass/ValencyD. Valency
Answer» Correct Answer - C

Discussion

30.	A current I is passed for a time t through a number of voltameters. If m is the mass of a substance deposited on an electrode and z is its electrochemical equivalent, thenA. `(zIt)/(m)` = constantB. `(z)/(mIt)` = constantC. `(I)/(zmt)` = constantD. `(It)/(zm)` = constant
Answer» Correct Answer - A

Discussion

31.	The mass of a substance liberated when a charge ‘ q ’ flows through an electrolyte is proportional toA. qB. 1/qC. `q^(2)`D. `1//q^(2)`
Answer» Correct Answer - A

Discussion

32.	In the process of electrolysis, the current is carried out inside the electrolyte byA. ElectronsB. AtomsC. Positive and negative ionsD. All the above
Answer» Correct Answer - C

Discussion

33.	In electrolysis the mass deposited on an electrode is directly proportional to:A. The currentB. The resistanceC. The temperatureD. The electric power
Answer» Correct Answer - A

Discussion

34.	For electroplating a spoon, it is placed in the voltameter atA. The position of anodeB. The position of cathodeC. Exactly in the middle of anode and the cathodeD. Anywhere in the electrolyte
Answer» Correct Answer - B

Discussion

35.	Electroplating does not help inA. Fine finish to the surfaceB. Shining appearanceC. Metals to become hardD. Protect metal against corrosion
Answer» Correct Answer - C

Discussion

36.	A thermocouple is made of Cu and Fe . If a battery is connected in it, thenA. Both junctions will be at the same temperatureB. Both junctions will become hotC. One junction will be hotter than the otherD. None of these
Answer» Correct Answer - C

Discussion

37.	The amount of heat produced in a resistor when a current is passed through it can be found usingA. Faraday’s LawB. Kirchhoff’s LawC. Laplace’s LawD. Joule’s Law
Answer» Correct Answer - D

Discussion

38.	If three bulbs 60 W , 100 W and 200 W are connected in parallel, thenA. 200 W bulb will glow moreB. 60 W bulb will glow moreC. 100 W bulb will glow moreD. All the bulbs will glow equally
Answer» Correct Answer - A

Discussion

39.	A bulb rated at (100 W – 200 V ) is used on a 100 V line. The current in the bulb isA. `(1)/(4) amp`B. `4 amp`C. `(1)/(2) amp`D. `2 amp`
Answer» Correct Answer - A

Discussion

40.	Two wires have resistance of `2 Omega` and `4 Omega` connected to same voltage, ratio of heat dissipated at resistance isA. `1 : 2`B. `4 : 3`C. `2 : 1`D. `5 : 2`
Answer» Correct Answer - C

Discussion

41.	A steel wire has a resistance twice that of an aluminium wire. Both of them are connected with a constant voltage supply. More heat will be dissipated inA. Steel wire when both are connected in seriesB. Steel wire when both are connected in parallelC. Aluminium wire when both are connected in seriesD. Aluminium wire when both are connected in parallel
Answer» Correct Answer - A::D

Discussion

42.	On giving 220 V to a resistor the power dissipated is 40 W then value of resistance isA. `1210 Omega`B. `2000 Omega`C. `1000 Omega`D. None of these
Answer» Correct Answer - A

Discussion

43.	An expression for rate of heat generated, if a current of I ampere flows through a resistance of `R Omega`, isA. `I^(2)Rt`B. `I^(2)R`C. `V^(2)R`D. `I R`
Answer» Correct Answer - B

Discussion

44.	A silver and a copper voltameter are connected in series with a `12.0 V` battery of negligible resistance. It is found that `0.806g` of silver is deposited in half an hour.Find (a) the mass of the copper deposited and (b) the energy supplied by the battery. `ECE` of silver `= 1.12 xx 10^(-6) kg C^(-1)` and that of copper `= 6.6 xx 10^(-7) kg C^(-1)`A. 64 WB. 32 WC. 96 WD. 16 W
Answer» Correct Answer - D

Discussion

45.	The chemical equivalent of silver is 108. If the current in a silver voltameter is 2 Amp. , the time required to deposit 27 grams of silver will beA. `8.57` hrsB. `6.70` hrsC. `3.35` hrsD. `12.50` hrs
Answer» Correct Answer - C

Discussion

46.	A `5.0` amp current is setup in an external circuit by a `6.0` volt storage battery for `6.0` minutes. The chemical energy of the battery is reduced byA. `1.08xx10^(4)J`B. `1.08xx10^(-4)` voltC. `1.8xx10^(4)J`D. `1.8xx10^(4)` volt
Answer» Correct Answer - A

Discussion

47.	For depositing 1 gm of Cu in copper voltameter on passing 2 amperes of current, the time required will be (For copper `Z = 0.00033` gm/C )A. Approx. 20 minutesB. Approx. 25 minutesC. Approx. 30 minutesD. Approx. 35 minutes
Answer» Correct Answer - B

Discussion

48.	A steady current of 5 amps is maintained for 45 mins . During this time it deposits `4.572` gms of zinc at the cathode of a voltameter. E.C.E. of zinc isA. `3.387xx10^(-4)gm//C`B. `3.387xx10^(-4)C//gm`C. `3.384xx10^(-3)gm//C`D. `3.394xx10^(-3)C//gm`
Answer» Correct Answer - A

Discussion

49.	A copper voltameter is connected in series with a heater coil of resistance `0.1 Omega` . A steady current flows in the circuit for twenty minutes and mass of 0.99 g of copper is deposited at the cathode. If electrochemical equivalent of copper is `0.00033` gm/C , then heat generated in the coil isA. 750 JB. 650 JC. 350 JD. 250 J
Answer» Correct Answer - A

Discussion

50.	A steady current of `1.5 A` flows through a copper voltameter for 10 min. If the electrochemical equivalent of copper is `30 xx 10^(-5) gC^(-1)`, the mass of copper deposited on the electrode will beA. `2.6xx10^(-5)m`B. `2.6xx10^(-4)m`C. `1.3xx10^(-5)m`D. `1.3xx10^(-4)m`
Answer» Correct Answer - C

Discussion

Explore topic-wise InterviewSolutions in .

For a thermocouple, the neutral temperature is `270^(@)C` and the temperature of its cold junction is `20^(@)C` . If there is no deflection in the galvanometer, the temperature of the hot junction should beA. `210^(@)C`B. `540^(@)C`C. `520^(@)C`D. `209^(@)C`

The neutral temperature of a thermocouple is `350^(@)C` when the cold junction is at . `0^(@)C` When the cold junction is immersed in a bath of `30^(@)C`, the inversion temperature isA. `700^(@)C`B. `600^(@)C`C. `35^(@)C`D. `670^(@)C`

A thermoelectric refrigerator works onA. Joule effectB. Seeback effectC. Peltier effectD. Thermonic emission

If a high power heater is connected to electric mains, then the bulbs in the house become dim, because there is aA. Current dropB. Potential dropC. No current dropD. No potential drop

Two bulbs, one of 50 watt and another of 25 watt are connected in series to the mains. The ratio of the currents through them isA. `2 : 1`B. `1 : 2`C. `1 : 1`D. Without voltage, cannot be calculated

4 bulbs marked 40 W , 250 V are connected in series with 250 V mains. The total power isA. 10 WB. 40 WC. 320 WD. 160 W

The current flowing through a lamp marked as 50 W and 250 V isA. 5 ampB. `2.5 amp`C. 2 ampD. `0.2 amp`

An electric lamp is marked 60 W , 230 V . The cost of a 1 kWh of energy is Rs . 1.25. The cost of using this lamp 8 hrs a day for 30 day isA. Rs. 10B. Rs. 16C. Rs. 18D. Rs. 20

Two electic bulbs rated `P_(1)` watt `V` volts and `P_(2)` watt `V` volts are connected in parallel and `V` volts are applied to it. The total power will beA. `P_(1)+P_(2)` wattB. `sqrt(P_(1)P_(2))` wattC. `(P_(1)P_(2))/(P_(1)+P_(2))` wattD. `(P_(1)+P_(2))/(P_(1)P_(2))` watt

Two electric bulbs A and B are rated as 60 W and 100 W . They are connected in parallel to the same source. Then,A. Both draw the same currentB. A draws more current than BC. B draws more current than AD. Current drawn are in the ratio of their resistances

A bulb has specification of one kilowatt and 250 volts , the resistance of bulb isA. `125 Omega`B. `62.5 Omega`C. `0.25 Omega`D. `625 Omega`

If in a voltaic cell 5 gm of zinc is consumed, then we get how many ampere hours ? (Given that E.C.E. of Zn is `3.387xx10^(-7)` kg/coulomb)A. `2.05`B. `8.2`C. `4.1`D. `5xx3.387xx10^(-7)`

If `2.2` kilowatt power is transmitted through a 10 ohm line at 22000 volt , the power loss in the form of heat will beA. `0.1` wattB. 1 wattC. 10 wattD. 100 watt

If a 2 kW boiler is used everyday for 1 hour, then electrical energy consumed by boiler in thirty days isA. 15 unitB. 60 unitC. 120 unitD. 240 unit

If `2.2` kW power is transmitted through a `100 Omega` line at , 000,22 V the power loss in the form of heat will beA. `0.1 W`B. 1 WC. 10 WD. 100 W

If for a thermocouple `T_(n))` is the neutral temperature, `T_(c )` is the tempreture of the cold junction and `T_(i))` is the temperature of inversion, thenA. `T_(i)=2T_(n)-T_(c )`B. `T_(n)=T_(i)-2T_(c )`C. `T_(i)=T_(n)-T_(c )`D. None of these

The cold junction of a thermocouple is maintained at `10^(@)C` . No thermo e.m.f . is developed when the hot junction is maintained at `530^(@)C` . The neutral temperature isA. `260^(@)C`B. `270^(@)C`C. `265^(@)C`D. `520^(@)C`

An electric bulb of 100 watt is connected to a supply of electricity of 220 V . Resistance of the filament isA. `484 Omega`B. `100 Omega`C. `22000 Omega`D. `242 Omega`

Who among the following scientists made the statement –"Chemical change can produce electricity"A. GalvaniB. FaradayC. CoulombD. Thomson

Peltier co-efficient of a thermo couple is 2 nano volts. How much heat is developed at a junction if 2.5 amp current flows for 2 minuteA. 6 ergsB. `6xx10^(-7)` ergsC. 16 ergsD. `6xx10^(-3)` erg

Peltier coefficient for the junction of a pair of metals is proportional toA. T absolute temperature of the junctionB. Square of absolute temperature of the junctionC. `(1)/("Absolute temperature of the junction")`D. `(1)/("Square of absolute temperature of the junction")`

The electrochemical equivalent Z of any element can be obtained by multiplying the electrochemical equivalent of hydrogen withA. Atomic weightB. Molecular weightC. Chemical equivalentD. A constant

The relation between faraday constant F , electron charge e and avogadro number N isA. F = N/eB. F = NeC. `N=F^(2)`D. `F = N^(2)e`

The electrochemical equivalent of a material depends onA. The nature of the materialB. The current through the electrolyteC. The amount of charge passed through electrolyteD. The amount of material present in electrolyte

The relation between faraday constant `(F)`, chemical equicalent `(E)` and electrochemical equivalent `(Z)` isA. `F = EZ`B. `F=(Z)/(E )`C. `F=(E )/(Z)`D. `F=(E )/(Z^(2))`

Faraday’s 2nd law states that mass deposited on the electrode is directly proportional toA. Atomic massB. Atomic mass × VelocityC. Atomic mass/ValencyD. Valency

A current I is passed for a time t through a number of voltameters. If m is the mass of a substance deposited on an electrode and z is its electrochemical equivalent, thenA. `(zIt)/(m)` = constantB. `(z)/(mIt)` = constantC. `(I)/(zmt)` = constantD. `(It)/(zm)` = constant

The mass of a substance liberated when a charge ‘ q ’ flows through an electrolyte is proportional toA. qB. 1/qC. `q^(2)`D. `1//q^(2)`

In the process of electrolysis, the current is carried out inside the electrolyte byA. ElectronsB. AtomsC. Positive and negative ionsD. All the above

In electrolysis the mass deposited on an electrode is directly proportional to:A. The currentB. The resistanceC. The temperatureD. The electric power

For electroplating a spoon, it is placed in the voltameter atA. The position of anodeB. The position of cathodeC. Exactly in the middle of anode and the cathodeD. Anywhere in the electrolyte

Electroplating does not help inA. Fine finish to the surfaceB. Shining appearanceC. Metals to become hardD. Protect metal against corrosion

A thermocouple is made of Cu and Fe . If a battery is connected in it, thenA. Both junctions will be at the same temperatureB. Both junctions will become hotC. One junction will be hotter than the otherD. None of these

The amount of heat produced in a resistor when a current is passed through it can be found usingA. Faraday’s LawB. Kirchhoff’s LawC. Laplace’s LawD. Joule’s Law

If three bulbs 60 W , 100 W and 200 W are connected in parallel, thenA. 200 W bulb will glow moreB. 60 W bulb will glow moreC. 100 W bulb will glow moreD. All the bulbs will glow equally

A bulb rated at (100 W – 200 V ) is used on a 100 V line. The current in the bulb isA. `(1)/(4) amp`B. `4 amp`C. `(1)/(2) amp`D. `2 amp`

Two wires have resistance of `2 Omega` and `4 Omega` connected to same voltage, ratio of heat dissipated at resistance isA. `1 : 2`B. `4 : 3`C. `2 : 1`D. `5 : 2`

On giving 220 V to a resistor the power dissipated is 40 W then value of resistance isA. `1210 Omega`B. `2000 Omega`C. `1000 Omega`D. None of these

An expression for rate of heat generated, if a current of I ampere flows through a resistance of `R Omega`, isA. `I^(2)Rt`B. `I^(2)R`C. `V^(2)R`D. `I R`

The chemical equivalent of silver is 108. If the current in a silver voltameter is 2 Amp. , the time required to deposit 27 grams of silver will beA. `8.57` hrsB. `6.70` hrsC. `3.35` hrsD. `12.50` hrs

A `5.0` amp current is setup in an external circuit by a `6.0` volt storage battery for `6.0` minutes. The chemical energy of the battery is reduced byA. `1.08xx10^(4)J`B. `1.08xx10^(-4)` voltC. `1.8xx10^(4)J`D. `1.8xx10^(4)` volt

For depositing 1 gm of Cu in copper voltameter on passing 2 amperes of current, the time required will be (For copper `Z = 0.00033` gm/C )A. Approx. 20 minutesB. Approx. 25 minutesC. Approx. 30 minutesD. Approx. 35 minutes

A steady current of 5 amps is maintained for 45 mins . During this time it deposits `4.572` gms of zinc at the cathode of a voltameter. E.C.E. of zinc isA. `3.387xx10^(-4)gm//C`B. `3.387xx10^(-4)C//gm`C. `3.384xx10^(-3)gm//C`D. `3.394xx10^(-3)C//gm`

A steady current of `1.5 A` flows through a copper voltameter for 10 min. If the electrochemical equivalent of copper is `30 xx 10^(-5) gC^(-1)`, the mass of copper deposited on the electrode will beA. `2.6xx10^(-5)m`B. `2.6xx10^(-4)m`C. `1.3xx10^(-5)m`D. `1.3xx10^(-4)m`