- 1UPSC CSE I - 2023Consider the following statements :
- In a seismograph, P waves are recorded earlier than S waves.
- In P waves, the individual particles vibrate to and fro in the direction of wave propagation whereas in S waves, the particles vibrate up and down at right angles to the direction of wave propagation.
Which of the statements given above is/are correct? - 2UPSC CSE I - 2013The known forces of nature can be divided into four classes, viz., gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct?
- 3UPSC CSE I - 2001
Consider the following statements:
In a nuclear reactor, self-sustained chain reaction is possible, because:
- More neutrons are released in each of the fission reactions.
- The neutrons immediately take part in the fission process.
- The fast neutrons are slowed down by graphite.
- Every neutron released in the fission reaction initiates further fission.
Which of these statements are correct?
- 4UPSC CSE I - 2001
Which one of the following is NOT radioactive?
- 5UPSC CSE I - 1999
Cobalt-60 is commonly used in radiation therapy because it emits
- 6UPSC CSE I - 1996
The alpha particle carries two positive charges. Its mass is very nearly equal to that of