Learning goal: to step through the application of =0 to prevent a crane from tipping over. a crane of weight w has a length (wheelbase) c, and its center of mass is midway between the wheels (i. e., the mass of the lifting arm is negligible). (figure 1) the arm extending from the front of the crane has a length b and makes an angle ? with the horizontal. the crane contacts the ground only at its front and rear tires. while watching the crane in operation, an observer mentions to you that for a given load there is a maximum angle ? max between 0? and 90? that the crane arm can make with the horizontal without tipping the crane over. is this correct? later that week, while watching the same crane in operation, a different observer mentions to you that there is a maximum load the crane can lift without tipping, and you can find that maximum load by observing the minimum angle ? min that the crane arm makes with the horizontal. is this correct?

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.

there are no components of a physical goal mentioned on the list of choices that you've provided.