MCQOPTIONS
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MCQOPTIONS
This section includes 255 Mcqs, each offering curated multiple-choice questions to sharpen your UPSEE knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
If the flux density through a spherical surface with radius ‘d’ enclosing a point charge Q, and â is the radial unit vector is \(\frac{Q}{{4\pi {d^2}}}\hat a\). Then the total flux coming out of the sphere is: |
| A. | Q |
| B. | \(\frac{Q}{{4\pi {d^2}}}\) |
| C. | 4πd2Q |
| D. | \(\frac{Q}{{4\pi {d^2}}}\hat a\) |
| Answer» B. \(\frac{Q}{{4\pi {d^2}}}\) | |
| 102. |
A sphere of radius r1 = 30 cm has a charge density \(\left(\rho\dfrac{r}{r_1}\right)\) where ρ0 = 200 pC / m3. The value of total change on the sphere is given by |
| A. | 34 pC |
| B. | 8.5 pC |
| C. | 17 pC |
| D. | 68 pC |
| Answer» D. 68 pC | |
| 103. |
A uniform line charge of ρL = 3μc/m lies along z-axis and a concentric circular cylinder of radius 2 m has surface charge density \({{\rho }_{s}}=-\frac{1.5}{4\pi }\mu c/{{m}^{2}}\). Both line and cylinder are infinity long z-axes. Compute the electric flux density \(\vec{D}\) for a region r > 2. |
| A. | \(\frac{0.477}{r}{{\hat{a}}_{r}}\left( \mu c/{{m}^{2}} \right)\) |
| B. | \(-\frac{0.477}{r}{{\hat{a}}_{r}}\left( \mu c/{{m}^{3}} \right)\) |
| C. | \(\frac{0.239}{r}{{\hat{a}}_{r}}\left( \mu c/{{m}^{2}} \right)\) |
| D. | \(-\frac{0.239}{r}{{\hat{a}}_{r}}\left( \mu c/{{m}^{3}} \right)\) |
| Answer» D. \(-\frac{0.239}{r}{{\hat{a}}_{r}}\left( \mu c/{{m}^{3}} \right)\) | |
| 104. |
Lorentz force law for a point charge \(\rm q\) is given by |
| A. | \(\rm F=q\left(\vec E +\vec v\times \vec B\right)\) |
| B. | \(\rm F=q\left(\vec E +\vec v\cdot \vec B\right)\) |
| C. | \(\rm F=q\left(\vec B +\vec v\times \vec E\right)\) |
| D. | \(\rm F=q\left(\vec B +\vec v\cdot \vec E\right)\) |
| Answer» B. \(\rm F=q\left(\vec E +\vec v\cdot \vec B\right)\) | |
| 105. |
Find the expression for the electric field at P (x, y, z) due to a point charge Q at origin. |
| A. | \(E = \frac{Q}{{4\pi \epsilon{{\left( {{x^2} + {y^2} + {z^2}} \right)}^2}}}\left( {x{a_x} + y{a_y} + z{a_z}} \right)\) |
| B. | \(E = \frac{Q}{{4\pi \epsilon{{\left( {{x^2} + {y^2} + {z^2}} \right)}^{\frac{3}{2}}}}}\left( {x{a_x} + y{a_y} + z{a_z}} \right)\) |
| C. | \(E = \frac{{{Q^2}}}{{4\pi \epsilon{{\left( {{x^2} + {y^2} + {z^2}} \right)}^2}}}\left( {x{a_x} + y{a_y} + z{a_z}} \right)\) |
| D. | \(E = \frac{{{Q^2}}}{{4\pi \epsilon{{\left( {{x^2} + {y^2} + {z^2}} \right)}^{\frac{3}{2}}}}}\left( {x{a_x} + y{a_y} + z{a_z}} \right)\) |
| Answer» C. \(E = \frac{{{Q^2}}}{{4\pi \epsilon{{\left( {{x^2} + {y^2} + {z^2}} \right)}^2}}}\left( {x{a_x} + y{a_y} + z{a_z}} \right)\) | |
| 106. |
Electron in atom are held in atom due to |
| A. | coulombs force |
| B. | nuclear force |
| C. | atomic force |
| D. | both coulombs force and nuclear force |
| Answer» B. nuclear force | |
| 107. |
A parallel plate air capacitor as shown below has a total charge Q and a breakdown voltage V. A slab of a dielectric constant 6 is inserted as shown. The maximum breakdown voltage and the charge at this voltage respectively would be |
| A. | V and 3.5 Q |
| B. | 3.5 V and Q |
| C. | \(\frac{V}{6}\) and 3Q |
| D. | 6V and 3Q |
| Answer» B. 3.5 V and Q | |
| 108. |
Electric flux ψ, is a ____ field, and its density D, is a ______ field. |
| A. | Scalar and scalar |
| B. | Vector and vector |
| C. | Vector and scalar |
| D. | Scalar and vector |
| Answer» E. | |
| 109. |
According to Gauss’s Law, the surface integral of the normal component of electric flux density D over a closed surface containing charge Q is: |
| A. | \(\frac{Q}{{{\varepsilon _0}}}\) |
| B. | ε0 Q |
| C. | Q |
| D. | \(\frac{{{Q^2}}}{{{\varepsilon _0}}}\) |
| Answer» D. \(\frac{{{Q^2}}}{{{\varepsilon _0}}}\) | |
| 110. |
______ is expressed as ratio of charge to potential difference. |
| A. | Electrical Capacitance |
| B. | Resistance |
| C. | Flux density |
| D. | Inductance |
| Answer» B. Resistance | |
| 111. |
Consider a long line charge of λ coulomb/meter perpendicular to the plane of a paper. The electrical field lines and equipotential surfaces are respectively |
| A. | radial, cylindrical concentric with a line charge |
| B. | Cylindrical concentric with line charge, radial |
| C. | radial, radial but opposite in direction |
| D. | concentric with line charge, parallel to a line charge |
| Answer» B. Cylindrical concentric with line charge, radial | |
| 112. |
If \(\vec E\) is the electric intensity, \(\nabla. \;\left( {\nabla \; \times \vec E} \right)\) is equal to |
| A. | \(\vec E\) |
| B. | \(\left| {\vec E} \right|\) |
| C. | null vector |
| D. | Zero |
| Answer» E. | |
| 113. |
A charge Q is located at (0, 0, 3) and -Q is located at (0, 0, -3). The electric filed intensity (E) at point (4, 0, 0) is: |
| A. | Negative X-direction |
| B. | Positive Y-direction |
| C. | Positive Z-direction |
| D. | Negative Z-direction |
| Answer» E. | |
| 114. |
5 equal capacitors connected in series have a resultant capacitance of 4 μF. When these are put in parallel and charged to 400 V, the total energy stored is: |
| A. | 16 J |
| B. | 8 J |
| C. | 4 J |
| D. | 2 J |
| Answer» C. 4 J | |
| 115. |
180 Coulombs of charge passes in a given time “t” through a wire of 1 ohm when connected to a 3 V DC supply. Identify the value of “t” from the options given |
| A. | 1 Minute |
| B. | 2 Minute |
| C. | 1.5 Minute |
| D. | 0.5 Minute |
| Answer» B. 2 Minute | |
| 116. |
If E = 0 at all points on a closed surface.1. The electric flux through the surface is zero2. The total charge enclosed by the surface is zero3. Charge resides on the surface |
| A. | 1 and 2 only |
| B. | 1 and 3 only |
| C. | 2 and 3 only |
| D. | 1, 2 and 3 |
| Answer» B. 1 and 3 only | |
| 117. |
Charge is distributed uniformly over the plane z = 10 cm with a density ρs = (1/3π) nC/m2. Find the magnitude of electric field intensity for z < 10 cm. |
| A. | 6 V/m |
| B. | 8 V/m |
| C. | 4 V/m |
| D. | 2 V/m |
| Answer» B. 8 V/m | |
| 118. |
Compute the amount of energy required to move a charge Q = 5μc from the origin to a point \(\left( 2m,\frac{\pi }{4},\frac{\pi }{2} \right)\) in a spherical co-ordinate system in the field \(\vec{E}=5{{e}^{-\frac{r}{4}}}{{\hat{a}}_{r}}+\frac{10}{rsin~\theta }{{\hat{a}}_{\phi }}\) |
| A. | 100 μJ |
| B. | 117.9 μJ |
| C. | -117.9 μJ |
| D. | -100 μJ |
| Answer» D. -100 μJ | |
| 119. |
Directions: Each of the next items consists of two statements, one labeled as the `Assertion (A)' and the other as 'Reason (R)' You are to examine these two statements carefully and select the answers to these items using the codes given below :Assertion (A): Good conductors do not show superconductivity.Reason (R): Electron-phonon interaction. that leads to the formation of Cooper pairs is weak in good conductors. |
| A. | Both A and R are individually true and R is the correct explanation of A |
| B. | Both A and R are individually true but R is not the correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» B. Both A and R are individually true but R is not the correct explanation of A | |
| 120. |
Direction: Question consists of two statements, one labeled as the 'Assertion (A)' and the other as 'Reason (R)'. Examine these two statements carefully and select the answer to this question using the codes given below:Assertion (A): In solving boundary value problems, the method of images is used.Reason (R): By this technique, conducting surfaces can be removed from the solution domain. |
| A. | Both A and R are individually true and R is the correct explanation of A |
| B. | Both A and R are individually true but R is not the correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» B. Both A and R are individually true but R is not the correct explanation of A | |
| 121. |
Orientational polarization is |
| A. | inversely proportional to temperature and proportional to the square of the permanent dipole moment |
| B. | proportional to temperature as well as to the square of the permanent dipole momen |
| C. | proportional to temperature and inversely proportional to the square of the permanent dipole moment |
| D. | inversely proportional to temperature as well as to the square of the dipole moment |
| Answer» B. proportional to temperature as well as to the square of the permanent dipole momen | |
| 122. |
The force between two charges is 120 N. If the distance between the charges is doubled, the force will be |
| A. | 60 N |
| B. | 30 N |
| C. | 40 N |
| D. | 15 N |
| Answer» C. 40 N | |
| 123. |
at a point may be defined as equal to the lines of force passing normally through a unit cross section at that point. |
| A. | Electric intensity |
| B. | Magnetic flux density |
| C. | Electric flux |
| D. | None of the above |
| Answer» B. Magnetic flux density | |
| 124. |
Dielectric strength of medium |
| A. | increases with rise in temperature |
| B. | increases with moisture content |
| C. | is same for all insulating materials |
| D. | none of the above |
| Answer» E. | |
| 125. |
A positive and a negative charge are initially 50 mm apart. When they are moved close together so that they are now only 10 mm apart, the force between them will be |
| A. | 5 times smaller than before |
| B. | 5 times greater than before |
| C. | 10 times greater than before |
| D. | 25 times larger than before |
| Answer» E. | |
| 126. |
The breakdown voltage for paper capacitors is usually |
| A. | 20 to 60 volts |
| B. | 200 to 1600 volts |
| C. | 2000 to 3000 volts |
| D. | more than 10000 volts |
| Answer» C. 2000 to 3000 volts | |
| 127. |
Dielectric strength of mica is |
| A. | 10 to 20 kV/mm |
| B. | 30 to 50 kV/mm |
| C. | 50 to 200 kV/mm |
| D. | 300 to 500 kV/mm |
| Answer» D. 300 to 500 kV/mm | |
| 128. |
Dielectric strength of a material depends on |
| A. | moisture content |
| B. | temperature |
| C. | thickness |
| D. | all of the above |
| Answer» E. | |
| 129. |
Electric displacement is a______quantity. |
| A. | scalar |
| B. | vector |
| C. | both of the above |
| D. | none of the above |
| Answer» C. both of the above | |
| 130. |
A capacitor having capacitance of 5 uF is charged to a potential difference of 10,000 V. The energy stored in the capacitor is |
| A. | 50 joules |
| B. | 150 joules |
| C. | 200 joules |
| D. | 250 joules |
| Answer» E. | |
| 131. |
If a 6 uF capacitor is charged to 200 V, the charge in coulombs will be |
| A. | 800 uC |
| B. | 900 uC |
| C. | 1200 uC |
| D. | 1600 uC |
| Answer» D. 1600 uC | |
| 132. |
A capacitor in a circuit became hot and ultimately exploded due to wrong connections, which type of capacitor it could be ? |
| A. | Paper capacitor |
| B. | Ceramic capacitor |
| C. | Electrolytic capacitor |
| D. | Any-of the above |
| Answer» D. Any-of the above | |
| 133. |
What is the value of capacitance that must be connected in parallel with 50 pF condenser to make an equivalent capacitance of 150 pF ? |
| A. | 50 pF |
| B. | 100 pF |
| C. | 150 pF |
| D. | 200 pF |
| Answer» C. 150 pF | |
| 134. |
Two infinite parallel plates 10 mm apart have maintained between them a potential difference of 100 V. The acceleration of an electron placed between them is |
| A. | 0.56 x 1015 m/s2 |
| B. | 1.5 x 1015 m/s2 |
| C. | 1.6 x 1015 m/s2 |
| D. | 1.76 x 1015 m/s2 |
| Answer» E. | |
| 135. |
Acharge which when placed in vacuum from an equal and similar charge repels with a force of 9 x 10 N, is known as |
| A. | milli-coulomb |
| B. | micro-coulomb |
| C. | pico-coulomb |
| D. | coulomb |
| Answer» C. pico-coulomb | |
| 136. |
_______ field is associated with the capacitor. |
| A. | Electric |
| B. | Magnetic |
| C. | Both (A) and (B) |
| D. | None of the above |
| Answer» B. Magnetic | |
| 137. |
The ability of charged bodies to exert force on 6ne another is attributed to the existence of |
| A. | electrons |
| B. | protons |
| C. | neutrons |
| D. | electric field |
| Answer» E. | |
| 138. |
If an ohmmeter reading immediately goes practically to zero and stays there, capacitor is |
| A. | Charged |
| B. | Short-circuited |
| C. | Lossy |
| D. | Satisfactory |
| Answer» C. Lossy | |
| 139. |
If A.C. voltage is applied to capacitive circuit, the alternating current can flow in the circuit because |
| A. | varying voltage produces the charging and dicharging currents |
| B. | of high peak value |
| C. | charging current can flow |
| D. | discharge current can flow |
| Answer» B. of high peak value | |
| 140. |
The number of Faraday tubes of flux passing through a surface in an electric field is called |
| A. | electric flux |
| B. | electric flux density |
| C. | magnetic flux density |
| D. | electric charge density |
| Answer» B. electric flux density | |
| 141. |
Which of the following capacitors will have the least variation? |
| A. | Paper capacitor |
| B. | Ceramic capacitor |
| C. | Silver plated mica capacitor |
| D. | None of the above |
| Answer» D. None of the above | |
| 142. |
Mica capacitors are characterised by all of the following except |
| A. | stable operation |
| B. | accurate value |
| C. | low leakage reactance |
| D. | low losses |
| Answer» D. low losses | |
| 143. |
If the sheet of a bakelite is inserted between the plates of an air capacitor, the capacitance will |
| A. | decrease |
| B. | increase |
| C. | remains unchanged |
| D. | become zero |
| Answer» C. remains unchanged | |
| 144. |
Three capacitors each of the capacity C are given. The resultant capacity 2/3 C can be obtained by using them |
| A. | all in series |
| B. | all in parallel |
| C. | two in parallel and third in series with this combination |
| D. | two in series and third in parallel across this combination |
| Answer» D. two in series and third in parallel across this combination | |
| 145. |
In a cable capacitor, voltage gradient is maximum at the surface of the |
| A. | earth |
| B. | conduction |
| C. | sheath |
| D. | insulator |
| Answer» C. sheath | |
| 146. |
“The surface integral of the normal component of the electric displacement D over any closed surface equals the charge enclosed by the surface”.The above statement is associated with |
| A. | Gauss’s law |
| B. | Kirchhoff's law |
| C. | Faraday’s law |
| D. | Lenz’s law |
| Answer» B. Kirchhoff's law | |
| 147. |
"The total electric flux through any closed surface surrounding charges is equal to the amount oflcharge enclosed".The above statement is associated with |
| A. | Coulomb’s square law |
| B. | Gauss’s law |
| C. | Maxwell’s first law |
| D. | Maxwell’s second law |
| Answer» C. Maxwell’s first law | |
| 148. |
This mention statement is associated with "The surface integral of the normal component of the electric displacement D over any closed surface equals the charge enclosed by the surface". |
| A. | Gauss's law |
| B. | Kirchhoff's law |
| C. | Faraday's law |
| D. | Lenz's law |
| Answer» B. Kirchhoff's law | |
| 149. |
For which of the following parameter variation, the capacitance of the capacitor remains unaffected ? |
| A. | Distance between plates |
| B. | Area of the plates |
| C. | Nature of dielectric |
| D. | Thickness of the plates |
| Answer» E. | |
| 150. |
An uncharged conductor is placed near a charged conductor, then |
| A. | the uncharged conductor gets charged by conduction |
| B. | the uncharged conductor gets charged by induction and then attracted towards the charging body |
| C. | the uncharged conductor is attracted first and then charged by induction |
| D. | it remains as such |
| Answer» C. the uncharged conductor is attracted first and then charged by induction | |