Physics – Class 12 Practice Test 9

1. On doping germanium metal, with a little amount of indium, what does one get?

2. A 300-day old radioactive substance shows an activity of 5000 dps, 150 days later its activity becomes 2500 dps. What was its initial activity?

3. Which will be the unknown nucleus formed when ²²Ne₁₀ decays into two α-particles and an unknown nucleus?

4. What is the energy released in a nuclear reaction called?

5. At absolute zero, Si acts as which of the following?

6. Who measured the size of the nucleus first?

7. The nuclear force is short-ranged.

8. Find out the application of the diode.

9. What is the energy released in the fission of 2 kg of Uranium 235? (Given: energy per fission = 200 MeV)

10. Solar energy is mainly caused due to fission of uranium present in the sun.