Question

A nucleus with mass number 220 initially at rest emits an alpha particle. If the Q value of reaction is 5.5 MeV, calculate the value of kinetic energy of alpha particle.

• A. 5.4 MeV
• B. 7.4 MeV
• C. 4.5 MeV
• D. 6.5 MeV

Answer 1

The Correct Option is A

Correct Answer: A

Explanation:

In a nuclear reaction, when a nucleus emits an alpha particle, the total energy released in the reaction is given by the Q value of the reaction. The Q value represents the total energy released, which is shared as kinetic energy between the products of the reaction.

In this case, the nucleus has a mass number of 220 and is initially at rest. It emits an alpha particle, and the Q value of the reaction is given as 5.5 MeV.

The energy released is shared between the alpha particle and the daughter nucleus. Since the daughter nucleus is much heavier than the alpha particle, the kinetic energy of the alpha particle will be very close to the Q value. The difference arises due to the mass ratio between the alpha particle and the daughter nucleus, but the kinetic energy of the alpha particle is approximately equal to the Q value.

Thus, the kinetic energy of the alpha particle is 5.4 MeV, which corresponds to the correct answer A.