A small rocket to gather weather data is launched straight up. Several seconds into the flight, its velocity is 140 m/s and it is accelerating at 20 m/s2 . At this instant, the rocket's mass is 51 kg and it is losing mass at the rate of 0.50 kg/s as it burns fuel. What is the net force on the rocket?

Explanation:

The force will be 98 N

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.

e/c, where e is its total energy