Mass–Energy Equivalence — Practice Quiz

Question 1

Energy released when 1 g of matter is fully converted to energy:

Accepted Answer

9 × 10¹³ J

Answer

3 × 10⁸ J

Answer

9 × 10¹⁰ J

Answer

1.6 × 10⁻¹⁹ J

Question 2

Mass defect equivalent to 1 MeV is:

Accepted Answer

≈ 1.78 × 10⁻³⁰ kg

Answer

1 u

Answer

10⁻²⁴ kg

Answer

9.1 × 10⁻³¹ kg

Question 3

1 u in MeV/c² is:

Accepted Answer

931.5

Answer

9.31

Answer

0.5

Answer

1240

Question 4

Pair production (γ → e⁺ + e⁻) requires minimum photon energy:

Accepted Answer

1.022 MeV

Answer

0.511 MeV

Answer

2.044 MeV

Answer

13.6 eV

Question 5

Energy of each γ when an electron and positron at rest annihilate:

Accepted Answer

0.511 MeV

Answer

1.022 MeV

Answer

0.255 MeV

Answer

Depends on direction