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If energy of photon is 5 MeV. Kinetic energy of particles after pair production is?
- 4 MeV
- 5 MeV
- 6 MeV
- Not enough information given
Energy of photon = Energy required for pair production + KE of particles. Now energy required for pair production is 1.02 MeV so KE is approximately equal to 5-1 = 4 MeV.
Physics of solids
A piece of Cu and another of Ge are cooled from room temp to -1500 C. The resistance of?
- Each of them increases
- Cu increases and that of Ge decreases
- Cu decrease and that of Ge increases
- Each of them decreases
Cu decrease and that of Ge increases
The resistivity of semiconductors increases with a decrease in the temperature while for conductors it decrease with a decrease in the temperature. As opposed to metals, semiconductors have high negative temperature.
The energy obtained in a nuclear reaction is derived from:
- Mass defect and binding energy
- All of these
All of these
The sum of the individual masses of the parts of a nucleus is less than their mass when they are bound into the nucleus producing mass defect. The mass from the mass defect is converted into the energy that holds the nucleus together and is released in fission. Fusion also produces energy when individual nuclei are forced to combine (fusion) and form new elements in a process that produces energy.