A golf ball slides down a pipe from the upper level of a miniature golf course and heads directly for the hole on the green. Unfortunately, an
other player's ball is directly in the way. The second ball, which is ini
tially at rest, moves forward with a speed of 3.0 m/s, causing it to land
in the cup. The first ball comes to a complete stop after the collision.
Both balls have a mass of 45 g. What is the first ball's speed before the
collision. |

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

explanation:

there is no change in the electric potential energy as it is in rest on both conditions.