Explanation:
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Answer:
speed of each marble after collision will be 1.728 m/sec
Explanation:
We have given mass of the marble 
Velocity of marble 
Its collides with other marble of mass 25 gram
So mass of other marble 
Second marble is at so 
We have to find the velocity of second marble
From momentum conservation we know that
, here v is common velocity of both marble after collision
So 
v = 1.428 m /sec
So speed of each marble after collision will be 1.728 m/sec
Alpha particles travel through the air they collide with oxygen and nitrogen molecules. While they collide with these molecules, they lose some energy until all energy are used up and they are absorbed. These particles can be absorbed by a sheet of paper or by the air. On the other hand, beta particles and gamma particles move faster than the alpha particles and are poor at ionizing atoms or molecules thus it takes more of the material to be able to absorb these particles.
Answer is C.
Optical microscope involves passing visible light transmitted through or reflected from the sample through a single or multiple lenses to allow a magnified view of the sample.