A filament bulb (\(500\) W, \(100\) V) is to be used in a \(230\) V main supply. When a resistance\(R\) is connected in series, the bulb works perfectly and consumes \(500\) W. The value of \(R\) is:

1. \(230\) Ω 2. \(46\) Ω
3. \(26\) Ω 4. \(13\) Ω

Subtopic:  Heating Effects of Current |
 66%
From NCERT
NEET - 2016
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The charge flowing through a resistance \(R\) varies with time \(t\) as \(Q=at-bt^2,\) where \(a\) and \(b\) are positive constants. The total heat produced in \(R\) is:
1. \(\dfrac{a^3R}{3b}\) 2. \(\dfrac{a^3R}{2b}\)
3. \(\dfrac{a^3R}{b}\) 4. \(\dfrac{a^3R}{6b}\)
Subtopic:  Heating Effects of Current |
 56%
From NCERT
NEET - 2016
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Two metal wires of identical dimensions are connected in series. If \(\sigma_1~\text{and}~\sigma_2\) are the conductivities of the metal wires respectively, the effective conductivity of the combination is:

1. \(\frac{2\sigma_1 \sigma_2}{\sigma_1+\sigma_2}\) 2. \(\frac{\sigma_1 +\sigma_2}{2\sigma_1\sigma_2}\)
3. \(\frac{\sigma_1 +\sigma_2}{\sigma_1\sigma_2}\) 4. \(\frac{\sigma_1 \sigma_2}{\sigma_1+\sigma_2}\)

Subtopic:  Derivation of Ohm's Law |
 63%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

\(\mathrm{A, B}~\text{and}~\mathrm{C}\) are voltmeters of resistance \(R\), \(1.5R\) and \(3R\) respectively as shown in the figure above. When some potential difference is applied between \(\mathrm{X}\) and \(\mathrm{Y}\), the voltmeter readings are \({V}_\mathrm{A}\), \({V}_\mathrm{B}\) and \({V}_\mathrm{C}\) respectively. Then:

       

1. \({V}_\mathrm{A} ={V}_\mathrm{B}={V}_\mathrm{C}\) 2. \({V}_\mathrm{A} \neq{V}_\text{B}={V}_\mathrm{C}\)
3. \({V}_\mathrm{A} ={V}_\mathrm{B}\neq{V}_\mathrm{C}\) 4. \({V}_\mathrm{A} \ne{V}_\mathrm{B}\ne{V}_\mathrm{C}\)

Subtopic:  Kirchoff's Voltage Law |
 65%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Across a metallic conductor of non-uniform cross-section, a constant potential difference is applied. The quantity which remains constant along the conductor is:
1. current density 2. current
3. drift velocity 4. electric field
Subtopic:  Current & Current Density |
 60%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The figure given below shows a circuit when resistances in the two arms of the meter bridge are \(5~\Omega\) and \(R\), respectively. When the resistance \(R\) is shunted with equal resistance, the new balance point is at \(1.6l_1\). The resistance \(R\) is: 
           
1. \(10~\Omega\)
2. \(15~\Omega\)
3. \(20~\Omega\)
4. \(25~\Omega\)

Subtopic:  Meter Bridge & Potentiometer |
 73%
From NCERT
AIPMT - 2014
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

The resistances of the four arms \(P,Q,R~\text{and}~S\) in a Wheatstone’s bridge are \(10~\Omega,30~\Omega,30~\Omega\) and \(90~\Omega\) respectively. The emf and internal resistance of the cell are \(7~\text{volt}\) and \(5~\Omega\) respectively. If the galvanometer resistance is \(50~\Omega\) the current drawn from the cell will be:
1. \(0.2~\text{A}\)
2. \(0.1~\text{A}\)
3. \(2.0~\text{A}\)
4. \(1.0~\text{A}\)
 
 
Subtopic:  Wheatstone Bridge |
 77%
From NCERT
AIPMT - 2013
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

If power dissipated in the \(9~\Omega\) resistor in the circuit shown is \(36\) W, the potential difference across the \(2~\Omega\) resistor will be:

            

1. \(8\) V
2. \(10\) V
3. \(2\) V
4. \(4\) V

Subtopic:  Heating Effects of Current |
 79%
From NCERT
AIPMT - 2011
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A current of \(2~\text{A}\) flows through a \(2~\Omega\) resistor when connected across a battery. The same battery supplies a current of \(0.5~\text{A}\) when connected across a \(9~\Omega\) resistor. The internal resistance of the battery is:

1. \(\dfrac{1}{3}~\Omega\) 2. \(\dfrac{1}{4}~\Omega\)
3. \(1~\Omega\) 4. \(0.5~\Omega\)
Subtopic:  EMF & Terminal Voltage |
 78%
From NCERT
AIPMT - 2011
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

The rate of increase of thermo-emf with the temperature at the neutral temperature of a thermocouple:
 
1. is zero.
2. depends upon the choice of the two materials of the thermocouple.
3. is negative.
4. is positive.
Subtopic:  Heating Effects of Current |
AIPMT - 2011
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links