MCQ 11 Mark
In the given figure, if the Wheatstone bridge is in balanced condition, then the value of resistance 'S' will be
- A12 Ω
- B9 Ω
- C3.0 Ω
- ✓6 Ω
Answer
View full question & answer→Correct option: D.
6 Ω
(d)6 Ω
Questions
M.C.Q [1M]
🎯
Test yourself on this topic
37 questions · timed · auto-graded
MCQ 21 Mark
The SI unit of resistivity is:
- A$\Omega / m$
- BΩ
- ✓Ωm
- DΩm²
Answer
View full question & answer→Correct option: C.
Ωm
(c )Ωm
MCQ 31 Mark
Electron and proton beams are travelling parallel to each other in the same direction. There will be ___________ between them.
- Aforce of attraction
- ✓force of repulsion
- Cneither attraction nor repulsion
- Dattractive or repulsive forces depends on the motion of the beams
Answer
View full question & answer→Correct option: B.
force of repulsion
(b)force of repulsion
MCQ 41 Mark
Magnitude of pursuit velocity does not depend on :
- Across-section of the wire
- ✓length of the wire
- Cthe number of free electrons
- Dmagnitude of current
Answer
View full question & answer→Correct option: B.
length of the wire
(b)length of the wire
MCQ 51 Mark
If resistance of a conductor is reduced to half and magnitude of current is doubled, then produced heat:
- Awill remain the same
- Bwill become half
- ✓will be double
- Dwill become four times
Answer
View full question & answer→Correct option: C.
will be double
(c )will be double
MCQ 61 Mark
I ampere current flows in a conducting wire for t seconds. If resistance of the wire is R ohms, then magnitude of produced heat in joules according to Joule's law is:
- ✓$I ^2 R t$
- B$IR ^2 t$
- C$\frac{t}{I^2 R}$
- D$\frac{ I ^2 R }{t}$
Answer
View full question & answer→Correct option: A.
$I ^2 R t$
(a)$I ^2 R t$
MCQ 71 Mark
Which of the following statement is correct in accordance with Kirchhoff's second law?
- AIn any closed circuit, algebraic sum of product of each resistance and current flowing through it is zero.
- ✓In any closed circuit, the algebraic sum of voltage moving in a particular direction is zero.
- CIn any closed circuit, algebraic sum of product of each resistance and current flowing through it is infinite.
- DIn any closed circuit, the algebraic sum of current flowing through each resistor is zero.
Answer
View full question & answer→Correct option: B.
In any closed circuit, the algebraic sum of voltage moving in a particular direction is zero.
(b)In any closed circuit, the algebraic sum of voltage moving in a particular direction is zero.
MCQ 81 Mark
Heat of 80 J is produced in a conductor on passing a current of 2 A for 10 seconds. The resistance of conductor will be:
- A0.5 ohms
- ✓2 ohms
- C4 ohms
- D0.4 ohms
Answer
View full question & answer→Correct option: B.
2 ohms
(b)2 ohms
MCQ 91 Mark
According to Kirchhoff's law, at any junction in an electric circuit:
- Aalgebraic sum of currents is negligible
- ✓algebraic sum of currents is zero
- Calgebraic sum of currents is infinite
- Dmagnitude of current is zero
Answer
View full question & answer→Correct option: B.
algebraic sum of currents is zero
(b)algebraic sum of currents is zero
MCQ 101 Mark
In interchanging the corresponding positions of battery and galvanometer in a Wheatstone bridge, the balanced position:
- ✓will remain unchanged
- Bwill change
- Ccan change or cannot change. It will depend on resistances of battery and galvanometer
- Dcannot say
Answer
View full question & answer→Correct option: A.
will remain unchanged
(a)will remain unchanged
MCQ 111 Mark
Relation between current (i) and drift velocity $\left(v_d\right)$ is :
- ✓$i=n e A v_d$
- B$i=\frac{n e A}{v_d}$
- C$i=\frac{n e v_d}{A}$
- D$i=\frac{n e}{A v_d}$
Answer
View full question & answer→Correct option: A.
$i=n e A v_d$
(a)$i=n e A v_d$
MCQ 121 Mark
If length of a conductor is doubled and cross-section is made half, then the specific resistance of the substance of changed wire will become:
- Ahalf
- Bdouble
- Cfour times
- ✓remains unchanged
Answer
View full question & answer→Correct option: D.
remains unchanged
(d)remains unchanged
MCQ 131 Mark
Cells are joined in parallel. The internal resistance of the cell is:
- Aequal to external resistance
- ✓more than the external resistance
- Cless than the external resistance
- Dnone of the above
Answer
View full question & answer→Correct option: B.
more than the external resistance
(b)more than the external resistance
MCQ 141 Mark
Two wires of same substance are given. Length and diameter of first wire are double that of the other. The resistance of first is __________ of other.
- Aequal
- ✓double
- Chalf
- Dfour times
Answer
View full question & answer→Correct option: B.
double
(b)double
MCQ 151 Mark
Resistivity of a wire depends on:
- Aits length
- Barea of its cross-section
- ✓its substance
- Dits shape
Answer
View full question & answer→Correct option: C.
its substance
(c )its substance
MCQ 161 Mark
Internal resistance of the cell is:
- Aresistance of electrode of the cell
- ✓resistance of electrolyte of the cell
- Cresistance of substance of the cell
- Dresistance of vessel of the cell
Answer
View full question & answer→Correct option: B.
resistance of electrolyte of the cell
(b)resistance of electrolyte of the cell
MCQ 171 Mark
Two resistance A and B are made up of same substance. Length and radius of wire A is twice that of B. Ratio of resistances of A and B are:
- ✓1:2
- B1:1
- C2:1
- D4:1
Answer
View full question & answer→Correct option: A.
1:2
(a)1:2
MCQ 181 Mark
Second law of Kirchhoff depends on the principle of conservation of:
- Acharge
- Bimpulse
- ✓energy
- Dsum of energy and mass
Answer
View full question & answer→Correct option: C.
energy
(c )energy
MCQ 191 Mark
Anelectron is revolving in an orbit of radius $5.1 \times 10^{-11} m$ is revolving with a frequency of $6.8 \times 10^{15} cycles / second$. The magnitude of equivalent current is :
- A$5.1 \times 10^{-3} A$
- B$6.8 \times 10^{-3} A$
- ✓$1.1 \times 10^{-3} A$
- D$2.2 \times 10^{-3} A$
Answer
View full question & answer→Correct option: C.
$1.1 \times 10^{-3} A$
(c )$1.1 \times 10^{-3} A$
MCQ 201 Mark
On joining a battery of 50 V with a resistance of $10 \Omega$, a current of 4.5 A flows through it. The internal resistance of the battery is :
- Azero
- ✓$1.1 \Omega$
- C$0.5 \Omega$
- D$500 \Omega$
Answer
View full question & answer→Correct option: B.
$1.1 \Omega$
(b)$1.1 \Omega$
MCQ 211 Mark
According to Ohm's law, relation between current density $j$ and intensity of electric field $E$ is :
- A$j=\frac{ I }{\sigma E }$
- B$E =\sigma j$
- C$j=\frac{\sigma}{ E }$
- ✓$j=\sigma E$
Answer
View full question & answer→Correct option: D.
$j=\sigma E$
(d)$j=\sigma E$
MCQ 221 Mark
The dependence of drift velocity on applied electric field E is:
- A$v_d$ will remain constant
- ✓$v_d \propto E$
- C$v_d \propto \frac{1}{ E }$
- Dnone of the above
Answer
View full question & answer→Correct option: B.
$v_d \propto E$
(b)$v_d \propto E$
MCQ 231 Mark
In the given figure, V-i graph of a conductor at two different temperatures is shown. If resistances corresponding to these temperatures are $R_1$ and $R _2$ respectively, then which of the following statement is correct ?
- A$T _1= T _2$
- B$T_1>T_2$
- ✓$T _1< T _2$
- Dnone of these
Answer
View full question & answer→Correct option: C.
$T _1< T _2$
(c )$T _1< T _2$
MCQ 241 Mark
Kirchhoff's second law in any closed circuit represents:
- ✓law of conservation of energy
- Blaw of conservation of charge
- Claw of conservation of current
- Dlaw of conservation of momentum
Answer
View full question & answer→Correct option: A.
law of conservation of energy
(a)law of conservation of energy
MCQ 251 Mark
Two wires of same size whose resistivities$\rho_1$ are $\rho_2$ and are joined in series. The equivalent resistivity of the combination will be:
- A$\sqrt{\rho_1 \rho_2}$
- B$2\left(\rho_1+\rho_2\right)$
- C$\rho_1+\rho_2$
- ✓$\rho_1+\rho_2$
Answer
View full question & answer→Correct option: D.
$\rho_1+\rho_2$
(d)$\rho_1+\rho_2$
MCQ 261 Mark
In random motion of free electrons in metals, the value of drift velocity $V _d$ in comparison with mean thermal velocity $V _0$ :
- A$v_d \approx V_o$
- B$v_d \gg V_o$
- ✓$v_d \ll V_o$
- Dnot definite
Answer
View full question & answer→Correct option: C.
$v_d \ll V_o$
(c )$v_d \ll V_o$
MCQ 271 Mark
A conducting resistor is joined with a battery. If the temperature of the conductor is changed with the cooling process, then the magnitude of current flowing:
- ✓will increase
- Bwill decrease
- Cwill remain constant
- Dwill become zero
Answer
View full question & answer→Correct option: A.
will increase
(a)will increase
MCQ 281 Mark
Resistance of the conductor depends upon:
- Aonly on the length of the conductor
- Bonly on the area of cross-section of the conductor
- Conly on the substance of the conductor
- ✓on all of the above
Answer
View full question & answer→Correct option: D.
on all of the above
(d)on all of the above
MCQ 291 Mark
Product of resistivity and conductivity of any conductor depends on:
- Aarea of cross-section
- Btemperature
- Clength
- ✓none of these
Answer
View full question & answer→Correct option: D.
none of these
(d)none of these
MCQ 301 Mark
10 C charge is passing through any point in electric circuit in 0.5 second. The magnitude of electric current in the circuit in amperes is:
- A10
- ✓20
- C0.005
- D0.5
Answer
View full question & answer→Correct option: B.
20
(b)20
MCQ 311 Mark
Kirchhoff's current rule depends on:
- Alaw of conservation of energy
- Blaw of conservation of momentum
- Claw of conservation of angular momentum
- ✓law of conservation of charge
Answer
View full question & answer→Correct option: D.
law of conservation of charge
(d)law of conservation of charge
MCQ 321 Mark
If current flowing through a conductor is doubled then the heat produced in it is:
- Adoubled
- Bhalf
- ✓four times
- Dsame
Answer
View full question & answer→Correct option: C.
four times
(c )four times
MCQ 331 Mark
Copper and germanium are cooled from room temperature to 30 K. In this process, the resistance:
- Awill decrease for both
- Bwill increase for both
- Cof copper will increase and of germanium will decrease
- ✓of copper will decrease and of germanium will increase
Answer
View full question & answer→Correct option: D.
of copper will decrease and of germanium will increase
(d)of copper will decrease and of germanium will increase
MCQ 341 Mark
Resistance of the metal increases with temperature because:
- ✓collision of conducting electrons with electrons increases
- Bcollision of conducting electrons with ions increases
- Cnumber of conducting electrons decreases
- Dnumber of conducting electrons increases.
Answer
View full question & answer→Correct option: A.
collision of conducting electrons with electrons increases
(a)collision of conducting electrons with electrons increases
MCQ 351 Mark
In a sensitive Wheatstone bridge, current in the galvanometer in the state of slight deflection from the position of balance is:
- Azero
- ✓more
- Cless
- Dnegligible
Answer
View full question & answer→Correct option: B.
more
(b)more
MCQ 361 Mark
Two similar cells, whether joined in series or in parallel, same current flows in external resistance of 2. The internal resistance of each cell is:
- A1 ohm
- ✓2 ohm
- C0.15 ohm
- D10 ohm
Answer
View full question & answer→Correct option: B.
2 ohm
(b)2 ohm
MCQ 371 Mark
When an ideal battery is joined with an external resistance in an electric circuit, a current i flows. through it. If another battery like this battery is joined in parallel with this battery, then the magnitude of current flowing in the battery will become:
- A$2 i$
- B$i$
- C$\frac{i}{2}$
- DZero