What type of force causes the motion of an object to change

Ok, so Unbalanced forces cause a change in motion, speed, and/or direction. When two forces act in the same direction on an object, the net force is equal to the sum of the two forces. In the example below, the net force would be 900 Newtons (450 + 450 = 900), and the object would move to the right.

Explanation:

Unbalanced forces cause a change in motion, speed, and/or direction. When two forces act in the same direction on an object, the net force is equal to the sum of the two forces.

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.