# The work functions of Caesium $$(\mathrm{Cs})$$, Potassium $$(\mathrm{K})$$ and Sodium $$(\mathrm{Na})$$ are $$2.14~\text{eV}$$, $$2.30~\text{eV}$$ and $$2.75~\text{eV}$$ respectively. If incident electromagnetic radiation has an incident energy of $$2.20~\text{eV}$$. which of these photosensitive surfaces may emit photoelectrons? 1. $$\mathrm{Na}$$ only 2. $$\mathrm{Cs}$$ only 3. Both $$\mathrm{Na}$$ and $$\mathrm{K}$$ 4. $$\mathrm{K}$$ only

Subtopic:  Photoelectric Effect: Experiment |
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NEET - 2023
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If $$\oint_s \vec{E} \cdot \overrightarrow{d S}=0$$ over a surface, then:

 1 the electric field inside the surface is necessarily uniform. 2 the number of flux lines entering the surface must be equal to the number of flux lines leaving it. 3 the magnitude of electric field on the surface is constant. 4 all the charges must necessarily be inside the surface.
Subtopic:  Gauss's Law |
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NEET - 2023
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Given below are two statements:
 Statement I: Photovoltaic devices can convert optical radiation into electricity. Statement II: Zener diode is designed to operate under reverse bias in the breakdown.
 1 Statement I is incorrect but Statement II is correct. 2 Both Statement I and Statement II are correct. 3 Both Statement I and Statement II are incorrect. 4 Statement I is correct but Statement II is incorrect.
Subtopic:  Applications of PN junction |
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NEET - 2023
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In a plane electromagnetic wave travelling in free space, the electric field component oscillates sinusoidally at a frequency of $$2.0\times 10^{10}~ \text{Hz}$$ and amplitude $$48~\text{Vm}^{-1}$$. Then the amplitude of the oscillating magnetic field is: (Speed of light in free space $$3\times 10^{8}~ \text{ms}^{-1}$$)
1. $$1.6 \times 10^{-6} ~\text{T}$$
2. $$1.6 \times 10^{-9} ~\text{T}$$
3. $$1.6 \times 10^{-8} ~\text{T}$$
4. $$1.6 \times 10^{-7} ~\text{T}$$
Subtopic:  Properties of EM Waves |
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From NCERT
NEET - 2023
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The temperature of a gas is $$-50^\circ \text{C}$$. To what temperature the gas should be heated so that the rms speed is increased by $$3$$ times?
 1 $$223~\text{K}$$ 2 $$669^\circ \text{C}$$ 3 $$3295^\circ \text{C}$$ 4 $$3097~\text{K}$$
Subtopic:  Types of Velocities |
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NEET - 2023
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The magnitude and direction of the current in the following circuit is:
 1 $$1.5~\text{A}$$ from $$\mathrm{B}$$ to $$\mathrm{A}$$ through $$E$$ 2 $$0.2~\text{A}$$ from $$\mathrm{B}$$ to $$\mathrm{A}$$ through $$E$$ 3 $$0.5~\text{A}$$  from $$\mathrm{A}$$ to $$\mathrm{B}$$ through $$E$$ 4 $$\dfrac{5}{9}~\text{A}$$ from $$\mathrm{A}$$ to $$\mathrm{B}$$ through $$E$$
Subtopic:  Kirchoff's Voltage Law |
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NEET - 2023
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An electric dipole is placed at an angle of $$30^\circ$$ with an electric field of intensity $$2\times 10^5 ~\text{NC}^{-1}$$. It experiences a torque equal to $$4~\text{N-m}$$. Calculate the magnitude of charge on the dipole if the dipole length is $$2~\text{cm}$$.
1. $$2~\text{mC}$$
2. $$8~\text{mC}$$
3. $$6~\text{mC}$$
4. $$4~\text{mC}$$
Subtopic:  Electric Dipole |
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NEET - 2023
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Let a wire be suspended from the ceiling (rigid support) and stretched by a weight $$W$$ attached at its free end. The longitudinal stress at any point of cross-sectional area $$A$$ of the wire is:
1. zero
2. $$\dfrac{2W}{A}$$
3. $$\dfrac{W}{A}$$
4. $$\dfrac{W}{2A}$$
Subtopic:  Stress - Strain |
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From NCERT
NEET - 2023
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The equivalent capacitance of the system shown in the following circuit is:

1. $$9~{\mu \text{F}}$$
2. $$2~{\mu \text{F}}$$
3. $$3~{\mu \text{F}}$$
4. $$6~{\mu \text{F}}$$
Subtopic:  Combination of Capacitors |
78%
From NCERT
NEET - 2023