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MCQOPTIONS
This section includes 12583 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.
| 12501. |
Equivalent resistance between the points A and B is (in W) [AMU (Engg.) 2000] |
| A. | \[\frac{1}{5}\] |
| B. | \[1\frac{1}{4}\] |
| C. | \[2\frac{1}{3}\] |
| D. | \[3\frac{1}{2}\] |
| Answer» D. \[3\frac{1}{2}\] | |
| 12502. |
A wire of resistance R is cut into ?n? equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be [MP PMT/PET 1998; BHU 2005] |
| A. | nR |
| B. | \[\frac{R}{n}\] |
| C. | \[\frac{n}{R}\] |
| D. | \[\frac{R}{{{n}^{2}}}\] |
| Answer» E. | |
| 12503. |
In the network shown in the figure, each of the resistance is equal to \[2\,\Omega \]. The resistance between the points A and B is [CBSE PMT 1995] |
| A. | \[1\,\Omega \] |
| B. | \[4\,\Omega \] |
| C. | \[3\,\Omega \] |
| D. | \[2\,\Omega \] |
| Answer» E. | |
| 12504. |
In a typical Wheatstone network, the resistances in cyclic order are A = 10 W, B = 5 W, C = 4 W and D = 4 W for the bridge to be balanced [KCET 2000] |
| A. | 10 W should be connected in parallel with A |
| B. | 10 W should be connected in series with A |
| C. | 5 W should be connected in series with B |
| D. | 5 W should be connected in parallel with B |
| Answer» B. 10 W should be connected in series with A | |
| 12505. |
Assertion : In practical application, power rating of resistance is not important. Reason : Property of resistance remain same even at high temperature. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| Answer» E. | |
| 12506. |
The equivalent resistance between P and Q in the given figure, is [MH CET (Med.) 2001] |
| A. | 50 W |
| B. | 40 W |
| C. | 30 W |
| D. | 20 W |
| Answer» E. | |
| 12507. |
The total current supplied to the circuit by the battery is [AIEEE 2004] |
| A. | 1 A |
| B. | 2 A |
| C. | 4 A |
| D. | 6 A |
| Answer» D. 6 A | |
| 12508. |
The current inside a copper voltameter [Roorkee 1992] |
| A. | Is half the outside value |
| B. | Is the same as the outside value |
| C. | Is twice the outside value |
| D. | Depends on the concentration of \[CuS{{O}_{4}}\] |
| Answer» C. Is twice the outside value | |
| 12509. |
The resistance of a galvanometer is 90 ohms. If only 10 percent of the main current may flow through the galvanometer, in which way and of what value, a resistor is to be used [MP PET 1996] |
| A. | 10 ohms in series |
| B. | 10 ohms in parallel |
| C. | 810 ohms in series |
| D. | 810 ohms in parallel |
| Answer» C. 810 ohms in series | |
| 12510. |
A 100 watt bulb working on 200 volt and a 200 watt bulb working on 100 volt have |
| A. | Resistances in the ratio of 4 : 1 |
| B. | Maximum current ratings in the ratio of \[1:4\] |
| C. | Resistances in the ratio of 2 : 1 |
| D. | Maximum current ratings in the ratio of 1 : 2 |
| Answer» C. Resistances in the ratio of 2 : 1 | |
| 12511. |
A current of 1 mA is flowing through a copper wire. How many electrons will pass a given point in one second \[\left[ e=\text{ }1.6\text{ }\times \text{ }{{10}^{19}}Coulomb \right]\] [RPMT 2000; MP PMT 2002] |
| A. | 6.25 × \[{{10}^{19}}\] |
| B. | 6.25 × \[{{10}^{15}}\] |
| C. | 6.25 × \[{{10}^{31}}\] |
| D. | 6.25 × \[{{10}^{8}}\] |
| Answer» C. 6.25 × \[{{10}^{31}}\] | |
| 12512. |
What is the equivalent resistance of the circuit [KCET 1998] |
| A. | \[6\,\Omega \] |
| B. | \[7\,\Omega \] |
| C. | \[8\,\Omega \] |
| D. | \[9\,\Omega \] |
| Answer» D. \[9\,\Omega \] | |
| 12513. |
For ensuring dissipation of same energy in all three resistors \[({{R}_{1}},\,{{R}_{2}},\,{{R}_{3}})\] connected as shown in figure, their values must be related as ] [AIIMS 2005] |
| A. | \[{{R}_{1}}={{R}_{2}}={{R}_{3}}\] |
| B. | \[{{R}_{2}}={{R}_{3}}\]and \[{{R}_{1}}=4{{R}_{2}}\] |
| C. | \[{{R}_{2}}={{R}_{3}}\]and \[{{R}_{1}}=\frac{1}{4}{{R}_{2}}\] |
| D. | \[{{R}_{1}}={{R}_{2}}+{{R}_{3}}\] |
| Answer» D. \[{{R}_{1}}={{R}_{2}}+{{R}_{3}}\] | |
| 12514. |
Given three equal resistors, how many different combination of all the three resistors can be made [NCERT 1970] |
| A. | Six |
| B. | Five |
| C. | Four |
| D. | Three |
| Answer» D. Three | |
| 12515. |
A certain piece of silver of given mass is to be made like a wire. Which of the following combination of length (L) and the area of cross-sectional will lead to the smallest resistance [MP PMT 1995; CBSE PMT 1997] |
| A. | L and A |
| B. | 2L and A/2 |
| C. | L/2 and 2 A |
| D. | Any of the above, because volume of silver remains same |
| Answer» D. Any of the above, because volume of silver remains same | |
| 12516. |
A wire is broken in four equal parts. A packet is formed by keeping the four wires together. The resistance of the packet in comparison to the resistance of the wire will be [MP PET 1985; AFMC 2005] |
| A. | Equal |
| B. | One fourth |
| C. | One eight |
| D. | \[\frac{1}{16}th\] |
| Answer» E. | |
| 12517. |
A thick wire is stretched so that its length become two times. Assuming that there is no change in its density, then what is the ratio of change in resistance of wire to the initial resistance of wire [MH CET 2004] |
| A. | 2 : 1 |
| B. | 4 : 1 |
| C. | 3 : 1 |
| D. | 1 : 4 |
| Answer» D. 1 : 4 | |
| 12518. |
In the figure, the value of resistors to be connected between C and D so that the resistance of the entire circuit between A and B does not change with the number of elementary sets used is |
| A. | R |
| B. | \[R(\sqrt{3}-1)\] |
| C. | 3 R |
| D. | \[R(\sqrt{3}+1)\] |
| Answer» C. 3 R | |
| 12519. |
Two batteries A and B each of e.m.f. 2 V are connected in series to an external resistance R = 1 ohm. If the internal resistance of battery A is 1.9 ohms and that of B is 0.9 ohm, what is the potential difference between the terminals of battery A [MP PET 2001] |
| A. | 2 V |
| B. | 3.8 V |
| C. | Zero |
| D. | None of the above |
| Answer» D. None of the above | |
| 12520. |
Four identical cells each having an electromotive force (e.m.f.) of 12V, are connected in parallel. The resultant electromotive force (e.m.f.) of the combination is [CPMT 1999] |
| A. | 48 V |
| B. | 12 V |
| C. | 4 V |
| D. | 3 V |
| Answer» C. 4 V | |
| 12521. |
Which of the following statement is false |
| A. | Heat produced in a conductor is proportional to its resistance |
| B. | Heat produced in a conductor is proportional to the square of the current |
| C. | Heat produced in a conductor is proportional to charge |
| D. | Heat produced in a conductor is proportional to the time for which current is passed |
| Answer» D. Heat produced in a conductor is proportional to the time for which current is passed | |
| 12522. |
Calculate the amount of charge flowing in 2 minutes in a wire of resistance 10 W when a potential difference of 20 V is applied between its ends [Kerala (Engg.) 2001] |
| A. | 120 C |
| B. | 240 C |
| C. | 20 C |
| D. | 4 C |
| Answer» C. 20 C | |
| 12523. |
A 25 watt, 220 volt bulb and a 100 watt, 220 volt bulb are connected in series across a 220 volt lines. Which electric bulb will glow more brightly [MP PET 1999; MP PMT 1999] |
| A. | 25 watt bulb |
| B. | 100 watt bulb |
| C. | First 25 watt and then 100 watt |
| D. | Both with same brightness |
| Answer» B. 100 watt bulb | |
| 12524. |
The resistance of a 5 cm long wire is 10 W. It is uniformly stretched so that its length becomes 20 cm. The resistance of the wire is [MH CET 2002] |
| A. | 160 W |
| B. | 80 W |
| C. | 40 W |
| D. | 20 W |
| Answer» B. 80 W | |
| 12525. |
How much work is required to carry a 6 mC charge from the negative terminal to the positive terminal of a 9 V battery [KCET (Med.) 2001] |
| A. | 54 × \[{{10}^{-3}}\]J |
| B. | 54 × \[{{10}^{-6}}\]J |
| C. | 54 × \[{{10}^{-9}}J\] |
| D. | 54 × \[{{10}^{-12}}\]J |
| Answer» C. 54 × \[{{10}^{-9}}J\] | |
| 12526. |
Calculate the power developed by an amplitude modulated wave in a load resistance of \[100\,\Omega ,\] if the peak voltage of carrier wave is \[100\text{ }V\] and modulation index is \[0.4\]. |
| A. | 50 watt |
| B. | 54 watt |
| C. | 104 watt |
| D. | 4 watt |
| Answer» C. 104 watt | |
| 12527. |
Maximum usable frequency (MUF) in F-region layer is x, when the critical frequency is \[60\text{ }MHz\]and the angle of incidence is \[70{}^\circ \]. Then calculate x. |
| A. | \[122\,MHz\] |
| B. | \[216\,Hz\] |
| C. | \[175\,MHz\] |
| D. | \[75\text{ }Hz\] |
| Answer» D. \[75\text{ }Hz\] | |
| 12528. |
The velocity of all radio waves in free space is \[3\times {{10}^{8}}m/s.\] What the frequency of a radio wave of wavelength is \[150\,m\]. |
| A. | \[5\,MHz\] |
| B. | \[2\,MHz\] |
| C. | \[0.5\,MHz\] |
| D. | \[0\,MHz\] |
| Answer» C. \[0.5\,MHz\] | |
| 12529. |
A carrier frequency of \[10\,kV\] at \[1\text{ }MHz\] is amplitude modulated by a \[1\text{ }kHz\] signal of \[6\text{ }kV\] peak voltage. When the modulation pattern is observed on a calibrated CRO, the voltage indicated by the CRO will be |
| A. | \[16\] |
| B. | \[32\] |
| C. | \[864\] |
| D. | \[84\] |
| Answer» C. \[864\] | |
| 12530. |
A modulated signal \[{{C}_{m}}(t)\] has the form \[{{C}_{m}}(t)=30\]\[\sin 300\pi t+10(\cos 200\pi t-\cos 400\pi t)\]. The carrier frequency \[{{f}_{c}},\] the modulating frequency (message frequency) \[{{f}_{\omega }}\] and the modulation index \[\mu \] are respectively given by : |
| A. | \[{{f}_{c}}=200\,Hz;\,{{f}_{w}}=50\,Hz;\,\,\mu =\frac{1}{2}\] |
| B. | \[{{f}_{c}}=150\,Hz;\,{{f}_{w}}=50\,Hz;\,\,\mu =\frac{2}{3}\] |
| C. | \[{{f}_{c}}=150\,Hz;\,{{f}_{w}}=30\,Hz;\,\,\mu =\frac{1}{3}\] |
| D. | \[{{f}_{c}}=200\,Hz;\,{{f}_{w}}=30\,Hz;\,\,\mu =\frac{1}{2}\] |
| Answer» C. \[{{f}_{c}}=150\,Hz;\,{{f}_{w}}=30\,Hz;\,\,\mu =\frac{1}{3}\] | |
| 12531. |
A broadcast radio transmitter radiates \[12\text{ }kW\]when percentage of modulation is 50%, then the unmodulated carrier power is |
| A. | \[5.67\,kW\] |
| B. | \[7.15\,kW\] |
| C. | \[9.6\text{ }kW\] |
| D. | \[12\text{ }kW\] |
| Answer» D. \[12\text{ }kW\] | |
| 12532. |
Band width is dependent on - |
| A. | the frequency of carrier |
| B. | the frequency of modulated signal |
| C. | the thickness of the cable |
| D. | the resistance of the circuit. |
| Answer» C. the thickness of the cable | |
| 12533. |
12 signals each band limited to \[5\text{ }kHz\] are to be transmitted by frequency-division multiplexer. If AM-SSB modulation guard band of \[\text{1 }kHz\] is used then the bandwidth of multiplexed signal is |
| A. | \[\text{101 }kHz\] |
| B. | \[\text{99 }kHz\] |
| C. | \[\text{84 }kHz\] |
| D. | \[\text{71 }kHz\] |
| Answer» E. | |
| 12534. |
Which of the following frequencies will be suitable for beyond-the horizon communication using sky waves? |
| A. | \[10\text{ }kHz\] |
| B. | \[10\text{ M}Hz\] |
| C. | \[\text{1 G}Hz\] |
| D. | \[\text{1000 G}Hz\] |
| Answer» C. \[\text{1 G}Hz\] | |
| 12535. |
An FM radio station operating at \[630\text{ }kHz\] is permitted to broadcast audio frequencies up to\[\text{6 }kHz\]. The band pass filter in its modulation circuit can retain the frequencies |
| A. | \[636\,kHz,\text{ }630\,kHz\] |
| B. | \[12\,kHz,\text{ }6\,kHz\] |
| C. | \[1260\,kHz,6\,kHz\] |
| D. | \[1260kHz,\text{ }630kHz\] |
| Answer» B. \[12\,kHz,\text{ }6\,kHz\] | |
| 12536. |
An oscillator is producing FM waves of frequency \[2\text{ }kHz\] with a variation of\[10\text{ }kHz\]. What is the modulating index? |
| A. | 5 |
| B. | 4 |
| C. | 3 |
| D. | 2 |
| Answer» B. 4 | |
| 12537. |
An audio frequency of \[10\text{ }kHz\] is transmitted by SSB after AM with carrier waves of frequency\[1\,MHz\]. The frequency of current in output load is |
| A. | \[1010\,kHz\] or \[990\,kHz\] |
| B. | \[1010\,MHz\] or \[1010\,MHz\] |
| C. | \[110\text{ }kHz\] or \[990\text{ }kHz\] |
| D. | \[110\text{ }MHz\] or \[990\text{ }MHz\] |
| Answer» B. \[1010\,MHz\] or \[1010\,MHz\] | |
| 12538. |
The most useful transmission for low frequency and small distance is through - |
| A. | sky waves |
| B. | ground waves |
| C. | surface waves |
| D. | space waves |
| Answer» C. surface waves | |
| 12539. |
When radio waves passes through ionosphere, phase difference between space current and capacitive displacement current is |
| A. | 0 rad |
| B. | \[(3\pi /2)\]rad |
| C. | \[(\pi /2)\]rad |
| D. | \[\pi \,rad\] |
| Answer» B. \[(3\pi /2)\]rad | |
| 12540. |
If the maximum amplitude of an amplitude modulated wave is \[25\text{ }V\] and the minimum amplitude is \[5\text{ }V,\] the modulation index is: |
| A. | \[\frac{1}{5}\] |
| B. | \[\frac{1}{3}\] |
| C. | \[\frac{3}{2}\] |
| D. | \[\frac{2}{3}\] |
| Answer» E. | |
| 12541. |
Space wave propagation is useful for - |
| A. | low frequency waves and large distances |
| B. | low frequency waves and small distances |
| C. | high frequency waves |
| D. | ultra-high frequency waves |
| Answer» E. | |
| 12542. |
An antenna is a device |
| A. | that converts electromagnetic energy into radio frequency signal |
| B. | that converts radio frequency signal into electromagnetic energy |
| C. | that converts guided electromagnetic waves into free space electromagnetic waves and vice-versa |
| D. | None of these |
| Answer» D. None of these | |
| 12543. |
Which range of frequencies is suitable for sky wave propagation? |
| A. | \[1\,kHz\] to \[500\,kHz\] |
| B. | \[1\,MHz\] to \[2\,MHz\] |
| C. | \[2\,MHz\] to \[20\,MHz\] |
| D. | Above \[30\,MHz\] |
| Answer» D. Above \[30\,MHz\] | |
| 12544. |
Long range radio transmission is possible when the radio waves are reflected from the ionosphere. For this to happen the frequency of the radio waves must be in the range: |
| A. | \[80-150\,MHz\] |
| B. | \[8-25MHz\] |
| C. | \[1-3\,MHz\] |
| D. | \[150-1500\,kHz\] |
| Answer» C. \[1-3\,MHz\] | |
| 12545. |
For the given combination of gates, if the logic states of inputs A, B, C are as follows A = B = C = C = 0 and A = B = 1, C = 0 then the logic states of output D are |
| A. | 0, 0 |
| B. | 0, 1 |
| C. | 1, 0 |
| D. | 1, 1 |
| Answer» C. 1, 0 | |
| 12546. |
In semiconductor the concentrations of electrons and holes are \[8\times {{10}^{18}}/{{m}^{3}}\] and \[5\times {{10}^{18}}/{{m}^{{}}}\] respectively. If the( mobilities of electrons and hole are \[2.3{{m}^{2}}\]/volt-sec and \[0.01{{m}^{2}}\]/volt-sec respectively, then semiconductor is |
| A. | \[N\]-type and its resistivity is 0.34 ohm-metre |
| B. | \[P\]-type and its resistivity is 0.034 ohm-metre |
| C. | \[N\]-type and its resistivity is 0.034 ohm-metre |
| D. | \[P\]-type and its resistivity is 3.40 ohm-metre |
| Answer» B. \[P\]-type and its resistivity is 0.034 ohm-metre | |
| 12547. |
The transistors provide good power amplification whes they are used in |
| A. | Common collector configuration |
| B. | Common emitter configuration |
| C. | Common base configuration |
| D. | None of these |
| Answer» C. Common base configuration | |
| 12548. |
Which state of triply ionised Baryllium\[(B{{e}^{+++}})\] has the same orbital radius as that of the ground state of hydrogen |
| A. | n = 4 |
| B. | n = 3 |
| C. | n = 2 |
| D. | n = 1 |
| Answer» D. n = 1 | |
| 12549. |
Energy of an electron in an excited hydrogen atom is - 3.4 eV. Its angular momentum will be: \[h=6.626\times {{10}^{-34}}J-s\] |
| A. | \[1.11\times {{10}^{34}}J\ \sec \] |
| B. | \[1.51\times {{10}^{-31}}J\ \sec \] |
| C. | \[2.11\times {{10}^{-34}}J\ \sec \] |
| D. | \[3.72\times {{10}^{-34}}J\ \sec \] |
| Answer» D. \[3.72\times {{10}^{-34}}J\ \sec \] | |
| 12550. |
The energy of hydrogen atom in its ground state is - 13.6 eV. The energy of the level corresponding to the quantum number n is equal 5 is |
| A. | - 5.40 eV |
| B. | - 2.72 eV |
| C. | - 0.85 eV |
| D. | - 0.54 eV |
| Answer» E. | |