مرکزی طبیعیات

Binding energy of a nucleus is the energy needed to:

• 1 Heat it
• 2 Rotate it
• 3 Add an electron
• 4 Separate it into nucleons

The mass defect is the difference between the:

• 1 Mass of two atoms
• 2 Mass of separate nucleons and the nucleus
• 3 Charge and mass
• 4 Atomic and mass number

A radioactive sample has a half life of 5 hours. After 15 hours the fraction left is:

• 1 1/2
• 2 1/4
• 3 1/8
• 4 1/3

Beta decay increases the atomic number by:

• 1 0
• 2 1
• 3 4
• 4 2

A fission chain reaction is controlled in a reactor using:

• 1 Water only
• 2 More uranium
• 3 Air
• 4 Control rods

The energy released from 1 atomic mass unit converted completely is about:

• 1 9310 MeV
• 2 931 MeV
• 3 9.31 MeV
• 4 93 MeV