- ARemains same
- BIncreases
- CDecreases
- DIncreases first and then decreases
Explanation:
As wavelength decrease, frequency increases and hence K.E of photoelectrons increases, thereby increasing the velocity.
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Figure given below shows two identical parallel plate capacitors connected to a battery with switch S closed. The switch is now opened and the free space between the plate of capacitors is filled with a dielectric of dielectric constant 3. What will be the ratio of total electrostatic energy stored in both capacitors before and after the introduction of the dielectric

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(a) 3 : 1 |
(b) 5 : 1 |
(c) 3 : 5 |
(d) 5 : 3 |
An electric dipole is placed in an electric field generated by a point charge
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(a) The net electric force on the dipole must be zero |
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(b) The net electric force on the dipole may be zero |
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(c) The torque on the dipole due to the field must be zero |
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(d) The torque on the dipole due to the field may be zero |
A conducting wire is moving towards right in a magnetic field B. The direction of induced current in the wire is shown in the figure. The direction of magnetic field will be

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(a) In the plane of paper pointing towards right |
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(b) In the plane of paper pointing towards left |
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(c) Perpendicular to the plane of paper and down‑wards |
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(d) Perpendicular to the plane of paper and upwards |
For a cell of e.m.f. 2V, a balance is obtained for 50 cm of the potentiometer wire. If the cell is shunted by a 2Ω resistor and the balance is obtained across 40 cm of the wire, then the internal resistance of the cell is
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(a) 0.25 Ω |
(b) 0.50 Ω |
(c) 0.80 Ω |
(d) 1.00 Ω |