A6.99-g bullet is moving horizontally with a velocity of +341 m/s, where the sign + indicates that it is moving to the right (see part a of the drawing). the bullet is approaching two blocks resting on a horizontal frictionless surface. air resistance is negligible. the bullet passes completely through the first block (an inelastic collision) and embeds itself in the second one, as indicated in part b. note that both blocks are moving after the collision with the bullet. the mass of the first block is 1202 g, and its velocity is +0.554 m/s after the bullet passes through it. the mass of the second block is 1523 g. (a) what is the velocity of the second block after the bullet imbeds itself? (b) find the ratio of the total kinetic energy after the collision to that before the collision.

a). 1.218 m/s

b). R=2.8

Explanation:

Momentum of the motion the first part of the motion have a momentum that is:

The final momentum is the motion before the action so:

a).

b).

kinetic energy

Kinetic energy after

Kinetic energy before

Ratio =

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.