As seen in class, lasers can be used as a tool for transforming cubes into almost perfect spheres at the microscale, as illustrated below. In this process, the volume of material is ideally unchanged after processing.
Select all the correct statements.

Question

As seen in class, lasers can be used as a tool for transforming cubes into almost perfect spheres at the microscale, as illustrated below. In this process, the volume of material is ideally  unchanged  after processing.  
  Select all the  correct  statements.

Answer

For this process, in fact the shorter the pulses the better!

Answer

For this operation, it is better to use a laser that is fully absorbed in the substrate so that the temperature reaches the melting point of the material.

Answer

The laser used for heating has a wavelength, which is highly absorbed by the material. Ideally it should be fully absorbed.

Answer

The cube is turned into a sphere, because the laser light gets trapped inside it, and creates radiation pressure on the cube edges that are gradually pushed into a sherical shapes.

Answer

The cube is turned into a sphere, as a sphere is the shape that minimizes surface energy when the material becomes liquid under the action of the laser.

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As seen in class, lasers can be used as a tool for transforming cubes into almos...

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