Consider the following pairs :
Objects in space: Description
1. Cepheids: Giant clouds of dust and gas in space
2. Nebulae: Stars which brighten and dim periodically
3. Pulsars: Neutron stars that are formed when massive stars run out of fuel and collapse
How many of the above pairs are correctly matched?
* Pair 1 is incorrect: Cepheids are actually stars that brighten and dim periodically, not giant clouds of dust and gas. * Pair 2 is incorrect: Nebulae are giant clouds of dust and gas in space, not stars that brighten and dim periodically. Thus, the first two pairs are reversed. * Pair 3 is correct: Pulsars are rapidly rotating neutron stars that are formed when massive stars exhaust their fuel and collapse. * So out of the 3 pairs given, only 1 pair (pair 3) is correctly matched.
Revision pages for syllabus ideas tested in this PYQ.