Answer
The answer and procedures of the exercise are attached in the following archives.
Step-by-step explanation:
You will find the procedures, formulas or necessary explanations in the archive attached below. If you have any question ask and I will aclare your doubts kindly.
<span>Answers: (a) 2.0 m/s (b) 4 m/s
Method:
(a) By conservation of momentum, the velocity of the center of mass is unchanged, i.e., 2.0 m/s.
(b) The velocity of the center of mass = (m1v1+m2v2) / (m1+m2)
Since the second mass is initially at rest, vcom = m1v1 / (m1+m2)
Therefore, the initial v1 = vcom (m1+m2) / m1 = 2.0 m/s x 6 = 12 m/s
Since the second mass is initially at rest, v2f = v1i (2m1 /m1+m2 ) = 12 m/s (2/6) = 4 m/s </span>
Answer:
The minimum speed of the box bottom of the incline so that it will reach the skier is 8.19 m/s.
Explanation:
It is given that,
Mass of the box, m = 2.2 kg
The box is inclined at an angle of 30 degrees
Vertical distance, d = 3.1 m
The coefficient of friction, 
Using the work energy theorem, the loss of kinetic energy is equal to the sum of gain in potential energy and the work done against friction.


W is the work done by the friction.







v = 8.19 m/s
So, the speed of the box is 8.19 m/s. Hence, this is the required solution.
Solution :
Mass of the particle = M
Speed of travel = v
Energy of one photon after the decay which moves in the positive x direction = 233 MeV
Energy of second photon after the decay which moves in the negative x direction = 21 MeV
Therefore, the total energy after the decay is = 233 + 21
= 254 MeV
So by the law of conservation of energy, we have :
Total energy before the decay = total energy after decay
So, the total relativistic energy of the particle before its decay = 254 MeV