3016: India-based Neutrino Observatory is included by the Planning Commission as a mega science project under the 11th five-Year Plan. In this context, consider the following statements:
1. Neutrinos are chargeless elementary particles that travel close to the speed of light.
2. Neutrinos are created in nuclear reactions of beta decay.
3. Neutrinos have a negligible, but nonzero mass.
4. Trillions of Neutrinos pass through human body every second.
Which of the statements given above are correct ?
(a) 1 and 3 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4
(d) 1, 2, 3 and 4
3017: Optical fibre works on the principle of
(a) total internal reflection
(b) refraction
(c) scattering
(d) interference
3018: The Ghadr (Ghadar) was a
(a) revolutionary association of Indians with headquarters at San Francisco
(b) nationalist organization operating from Singapore
(c) militant organization with headquarters at Berlin
(d) communist movement for India's freedom with headquarters at Tashkent
3019: Consider the following:
The arrival of Babur into India led to the
1. introduction of gunpowder in the subcontinent
2. introduction of the arch and dome in the region's architecture
3. establishment of Timurid dynasty in the region
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
3020: The chemical used as a 'fixer' in photography is
(a) sodium sulphate
(b) sodium thiosulphate
(c) ammonium persulphate
(d) borax