Which of the following pairs of physical phenomenon and the discoverer is/are correctly matched? 1. James Chadwick : Photoelectric effect 2. Albert Einstein : Neutron 3. Marie Curie : Radium Select the correct answer using the code given below:
- A.1, 2 and 3
- B.1 and 2 only
- C.2 and 3 only
- D.3 only
Correct answer
Explanation
The correct answer is D, 3 only. Marie Curie discovered radium; the first two pairs have their discoveries swapped.
Marie Curie and Pierre Curie discovered the radioactive elements polonium and radium in 1898, and Marie Curie went on to win Nobel Prizes in both physics (1903) and chemistry (1911). James Chadwick discovered the neutron in 1932 and received the 1935 Nobel Prize in physics. Albert Einstein explained the photoelectric effect in 1905 using light quanta, and it was this work, not relativity, that earned him the 1921 Nobel Prize in physics.
A is wrong: pairs 1 and 2 are mismatched, so all three cannot be correct.
B is wrong: Chadwick is linked with the neutron and Einstein with the photoelectric effect, so both pairs are wrong.
C is wrong: pair 2 is wrong because Einstein did not discover the neutron.
Exam tip: electron, J.J. Thomson; proton, Rutherford; neutron, Chadwick; radium, Marie Curie; photoelectric effect explained, Einstein.
Practice Questions
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Show answer
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