Their combined momentum after they meet is 0 .
Answer:
In order to improve visibility
Explanation:
Infrared telescopes are made using infrared cameras that contain infrared detectors which are solid-state and are maintained at very cold (cryogenic) temperatures
Infrared radiation is absorbed by water vapor which is present in the Earth's atmosphere, leading to the limitation of the use of infra red telescopes at high altitudes such as mountains, high flying planes or satellites
When silver is poured into the mould the it will solidify
In this process the phase of the Silver block will change from liquid to solid.
This phase change will lead to release in heat and this heat is known as latent heat of fusion.
The formula to find the latent heat of fusion is given as

here given that


now we can find the heat released


So it will release total heat of 55.5 kJ when it will solidify