The Dyson sphere is an hypothetical spherical structure centered around a star. Inspired by a science fiction story, physicist Freeman Dyson described such a structure for the first time in a scientific paper in 1959. His basic idea consisted of an artificial spherical structure of matter built around a star at a distance comparable to a planetary orbit, with the purpose of capturing the energy radiated by the star and reusing it for industrial purposes. Assume the mass of the sun to be 2.00 x 10^30 kg .
(a) Consider a solid, rigid spherical shell with a thickness of 100 m and a density of 3900 kg/m^3 . The sphere is centered around the sun so that its inner surface is at a distance of 1.50 x 10^11 m from the center of the sun. What is the net force that the sun would exert on such a Dyson sphere were it to get displaced off-center by some small amount?
Express your answer numerically in newtons.

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.

hypothesising or postulating