The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section, and same material is \(0.25~\Omega\). What will be the effective resistance if they are connected in series?
1. \(1~\Omega\) 
2. \(4~\Omega\)
3. \(0.25~\Omega\)
4. \(0.5~\Omega\)

Subtopic:  Combination of Resistors |
 72%
Level 2: 60%+
NEET - 2021
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A radioactive nucleus \(_{\mathrm{Z}}^{\mathrm{A}}\mathrm{X}\) undergoes spontaneous decay in the sequence \(_{\mathrm{Z}}^{\mathrm{A}}\mathrm{X}\rightarrow \mathrm{B}_{\mathrm{Z-1}}\rightarrow \mathrm{C}_{\mathrm{Z-3}}\rightarrow \mathrm{D}_{\mathrm{Z-2}}\) where \(\mathrm{Z}\) is the atomic number of element \(\mathrm{X}.\) The possible decay particles in the sequence are: 
1. \(\beta^{+}, ~\alpha, ~\beta^{-}\) 2. \(\beta^{-}, ~\alpha, ~\beta^{+}\)
3. \(\alpha, ~\beta^{-},~\beta^{+}\) 4. \(\alpha, ~\beta^{+},~\beta^{-}\)
Subtopic:  Types of Decay |
 74%
Level 2: 60%+
NEET - 2021
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A dipole is placed in an electric field as shown. In which direction will it move? 

           

1. towards the left as its potential energy will decrease.
2. towards the right as its potential energy will increase.
3. towards the left as its potential energy will increase.
4. towards the right as its potential energy will decrease.
Subtopic:  Electric Dipole |
Level 3: 35%-60%
NEET - 2021
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An inductor of inductance \(L\), a capacitor of capacitance \(C\) and a resistor of resistance \(R\) are connected in series to an AC source of potential difference \(V\) volts as shown in Figure. The potential difference across \(L\), \(C\) and \(R\) is \(40~\text{V}\), \(10~\text{V}\) and \(40~\text{V}\), respectively. The amplitude of the current flowing through the \(LCR\) series circuit is \(10\sqrt{2}~\text{A}\). The impedance of the circuit will be:


1. \(4~\Omega\)
2. \(5~\Omega\)
3. \(4\sqrt{2}~\Omega\)
4. \(\dfrac{5}{\sqrt{2}}~\Omega\)

Subtopic:  Different Types of AC Circuits |
Level 3: 35%-60%
NEET - 2021
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The equivalent capacitance of the combination shown in the figure is:

1. \(\dfrac{C}{2}\)
2. \(\dfrac{3C}{2}\)
3. \(3C\)
4. \(2C\)

Subtopic:  Combination of Capacitors |
 58%
Level 3: 35%-60%
NEET - 2021
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Given below are two statements:
Statement A: A Zener diode is connected in reverse bias when used as a voltage regulator.
Statement B: The potential barrier of \(\mathrm{p\text-n}\) junction lies between \(0.2\) V to \(0.3\) V.
 
1. Statement A is correct and Statement B is incorrect.
2. Statement A is incorrect and Statement B is correct.
3. Statement A and Statement B both are correct.
4. Statement A and Statement B both are incorrect.
Subtopic:  Applications of PN junction |
 52%
Level 3: 35%-60%
NEET - 2021
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For a plane electromagnetic wave propagating in the \(x\)-direction, which one of the following combinations gives the correct possible directions for the electric field \((E)\) and magnetic field \((B)\) respectively?
1. \(\hat{j}+\hat{k},~-\hat{j}-\hat{k}\) 2. \(-\hat{j}+\hat{k},~-\hat{j}+\hat{k}\)
3. \(\hat{j}+\hat{k},~\hat{j}+\hat{k}\) 4. \(-\hat{j}+\hat{k},~-\hat{j}-\hat{k}\)
Subtopic:  Properties of EM Waves |
Level 3: 35%-60%
NEET - 2021
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The number of photons per second on an average emitted by a source of monochromatic light of wavelength \(600~\text{nm}\), when it delivers the power of \(3.3\times 10^{-3}\) watt will be:\((h = 6.6\times10^{-34}~\text{J-s})\)
1. \(10^{16}\)
2. \(10^{15}\)
3. \(10^{18}\)
4. \(10^{17}\)
Subtopic:  Particle Nature of Light |
 67%
Level 2: 60%+
NEET - 2021
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A parallel plate capacitor has a uniform electric field \(\vec{E}\) in the space between the plates. If the distance between the plates is \(d\) and the area of each plate is \(A\) the energy stored in the capacitor is: 
\(\left ( \varepsilon_{0} = \text{permittivity of free space} \right )\)

1. \(\dfrac{1}{2}\varepsilon_0 E^2 Ad\) 2. \(\dfrac{E^2 Ad}{\varepsilon_0}\)
3. \(\dfrac{1}{2}\varepsilon_0 E^2 \) 4. \(\varepsilon_0 EAd\)
Subtopic:  Energy stored in Capacitor |
 74%
Level 2: 60%+
NEET - 2021
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A capacitor of capacitance \(C\) is connected across an AC source of voltage \(V\), given by;
\(V=V_0 \sin \omega t\)
The displacement current between the plates of the capacitor would then be given by:
1. \( I_d=\dfrac{V_0}{\omega C} \sin \omega t \) 2. \( I_d=V_0 \omega C \sin \omega t \)
3. \( I_d=V_0 \omega C \cos \omega t \) 4. \( I_d=\dfrac{V_0}{\omega C} \cos \omega t\)
Subtopic:  Displacement Current |
 59%
Level 3: 35%-60%
NEET - 2021
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