The initial momentum of the system can be expressed as,

The final momentum of the system can be given as,

According to conservation of momentum,

Plug in the known expressions,

Initially, the second mass move towards the first mass therefore the initial speed of second mass will be taken as negative and the recoil velocity of first mass is also taken as negative.
Plug in the known values,

Thus, the final velocity of second mass is 2.99 m/s.
Answer: Real image
Explanation:
converging lens will only produce a real image if the object is located beyond the focal point (i.e., more than one focal length away).
Answer:
Sound waves are pushed closer together, decreasing wavelength
and increasing frequency.
<h2>Answer:</h2>
The diagram is not showing the second law of thermodynamics. It is the demonstration of 1st law of thermodynamics.
<h3>Explanation:</h3>
Second law of thermodynamics describes the entropy of the system increase with time, it does not decrease with time. It is constant for ideal systems.
While in first law of thermodynamics, it is stated that the energy of a system can not be lost but it is transferred from one form to other form.
And in this picture, it is shown that the energy released from heat source to cold sink is used in doing work.
Work and heat are forms of energy.
The doppler effect is the increase or decrease in the frequency of sound, light, or other waves as the source and observer move toward or away from each other.