جوہری اور مرکزی طبیعیات

دسویں جماعت · طبیعیات · 5 سوالات

نام: ____________________ تاریخ: ____________

Which radiation is the most penetrating?
- A All equal
- B Gamma
- C Alpha
- D Beta
An alpha particle is the same as a:
- A Hydrogen nucleus
- B Helium nucleus
- C Neutron
- D Electron
A sample has a half life of 4 days. What fraction remains after 12 days?
- A 1/16
- B 1/8
- C 1/4
- D 1/2
The splitting of a heavy nucleus into lighter nuclei is called:
- A Fission
- B Fusion
- C Ionisation
- D Evaporation
The energy of the Sun comes from nuclear:
- A Fusion
- B Fission
- C Combustion
- D Decay only

جوابی کلید

1. B, 2. B, 3. B, 4. A, 5. A

Gamma rays pass through most materials and need thick lead or concrete to stop them.
An alpha particle is two protons and two neutrons, a helium nucleus.
12 days is 3 half lives, so (1/2)^3 = 1/8.
This is nuclear fission, as in a nuclear power plant.
Hydrogen nuclei fuse to form helium in the Sun.