# Speed of a unit vector

## Homework Statement

Givens:
An object with a mass of 2kg has a momentum of p=<-1,-2,3>. The first two questions asked for the magnitude of the momentum and the corresponding unit vector, which i found to be 3.74 and <-0.267,-0.535,0.802> respectively. The next question asks for the speed of the object, which is where i am having trouble. Ive looked everywhere for how to determine the speed of an object from its unit vector and cannot seem to find an answer. I believe im either overlooking something simple or am simply missing a vital piece of information.

Orodruin
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What makes you think that you need to use the unit vector?

As i was typing out "but its the only thing i was given" i realized i totally forgot about the first vector set. So the correct thing to do would be to multiply the <-1,-2,3> by 2, and then take the magnitude of that? Sorry for the original post im under a lot of stress as its a sort of pop quiz that we have limited time to finish.

Orodruin
Staff Emeritus