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Q & A: Can you determine the mass of an object in free space?

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Most recent answer: 05/26/2015
in an environment of complete absence of any gravitational force how the mass of a body can be determined
- T K Ray (age 71)
Kolkata, India

Hi T K,

You can use the law of conservation of momentum to compare the mass of the unknown object to a mass standard such as the International Prototype Kilogram (IPK).   .  What you have to do is to launch the standard mass toward the unknown mass and measure all the velocities both before and after the collision.  Then if the collision is co-linear  MstandardVinitial  = MsVfinal + Munknown Uunknown  .   This is easily solved for Munknown .  If the collision is not co-linear you have to use some trigonometry to make sure on-axis and off-axis components add up properly. 




(published on 05/26/2015)

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