- The wavelength is higher.
- The intensity is higher.
- The frequency is higher.
- The photon energy is higher.
Explanation:
Harder X-rays are the X-rays having low wavelengths. Since the frequency varies inversely with the wavelength, hard X-rays have high frequency.
Energy of a photon (E) is given by
$\text{E}=\frac{\text{hc}}{\lambda}$
Here,
h = Planck's constant
c = Speed of light
$\lambda$ = Wavelength of light.
Clearly, energy varies inversely with wavelength. Therefore, the energy of the photon will be higher for the hard X-ray.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Points A and B are situated perpendicular to the axis of a 2cm long bar magnet at large distances X and 3X from its centre on opposite sides. The ratio of the magnetic fields at A and B will be approximately equal to
|
(a) 1 : 9 |
(b) 2 : 9 |
(c) 27 : 1 |
(d) 9 : 1 |
+ 2C and +6C two charges are repelling each other with a force of 12N. If each charge is given -2C of charge, then the value of the force will be
|
(a) 4N (Attractive) |
(b) 4N (Repulsive) |
(c) 8N (Repulsive) |
(d) Zero |
Semiconductor is damaged by the strong current due to
|
(a) Lack of free electron |
(b) Excess of electrons |
|
(c) Excess of proton |
(d) None of these |
The e.m.f. of a cell is E volts and internal resistance is r ohm. The resistance in external circuit is also r ohm. The p.d. across the cell will be
|
(a) E/2 |
(b) 2E |
(c) 4E |
(d) E/4 |
In an amplifier the load resistance
is equal to the plate resistance (
. The voltage amplification is equal to
|
(a) μ |
(b) 2 μ |
(c) μ/2 |
(d) μ/4 |
A magnetic field
|
(a) Always exerts a force on a charged particle |
|
(b) Never exerts a force on a charged particle |
|
(c) Exerts a force, if the charged particle is moving across the magnetic field lines |
|
(d) Exerts a force, if the charged particle is moving along the magnetic field lines |
The mass of a neutron is the same as that of
|
(a) A proton |
(b) A meson |
(c) An epsilon |
(d) An electron |
Find out the e.m.f. produced when the current changes from 0 to 1 A in 10 second, given L = 10 mH
|
(a) 1 V |
(b) 1 mV |
(c) 1 mV |
(d) 0.1 V |