- ✓Convex
- BConcave
- CCylindrical
- DPlano-Convex
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When the current flowing in a circular coil is doubled and the number of turns of the coil in it is halved, the magnetic field at its centre will become
|
(a) Four times |
(b) Same |
(c) Half |
(d) Double |
Three capacitors of 2μF, 3μF and 6μF are joined in series and the combination is charged by means of a 24 volt battery. The potential difference between the plates of the 6 μF capacitor is
|
(a) 4 volt |
(b) 6 volt |
(c) 8 volt |
(d) 10 volt |
The energy of an X- ray photon of wavelength 1.65 Å is (h = 6.6
, 1eV = 1.6 ![]()
|
(a) 3.5 keV |
(b) 5.5 keV |
(c) 7.5 keV |
(d) 9.5 keV |
A charged particle is moving with velocity v in a magnetic field of induction B. The force on the particle will be maximum when
|
(a) v and B are in the same direction |
(b) v and B are in opposite directions |
|
(c) v and B are perpendicular |
(d) v and B are at an angle of 45° |
X-rays region lies between
| (a) Short radiowave and visible region | (b) Visible and ultraviolet region |
| (c) Gamma rays and ultraviolet region | (d) Short radiowave and long radiowave |
For a nucleus to be stable, the correct relation between neutron number N and Proton number Z is
|
(a) N > Z |
(b) N = Z |
(c) N < Z |
(d) N ≥ Z |