Abar of steel has the minimum properties se = 40 kpsi, sy = 60 kpsi, and sut = 80 kpsi. the bar is subjected to a steady torsional stress of 15 kpsi and an alternating bending stress of 25 kpsi. find the factor of safety guarding against a static failure, and either the factor of safety guarding against a fatigue failure or the expected life of the part. for the fatigue analysis use: a) modified goodman criterion. b) gerber criterion. c) asme-elliptic criterion.

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.

gravity

explanation: