Momentum in Space - How long will it take?

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An astronaut, weighing 66kg, is 45.3m away from her shuttle and initially at rest. She throws a 0.912kg camera at a speed of 12m/s to propel herself back. Using the conservation of momentum, the astronaut's velocity is calculated to be approximately 0.165m/s. The time taken to reach the shuttle is then computed as 274 seconds, or about 4.6 minutes. However, the solution was marked incorrect, prompting a request for assistance with the arithmetic.
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Momentum in Space --- How long will it take..?

Homework Statement



A 66kg astronaut becomes separated from the shuttle while on a space walk. She finds herself 45.3m away from the shuttle and moving with zero speed relative to the shuttle. She has a .912kg camera in her hand and decides to get back to the shuttle by throwing the camera at a speed of 12m/s in the opposite direction. How long will it take her to reach the shuttle? Answer in mins.

Homework Equations


p=m*v
m1*v1=m2*v2
v=d/t


The Attempt at a Solution


Since it is in space, I know that the momentum of the camera will equal that of the astronaut. So MassofCamera * VelocityOfCamera = MassOfAstronaut * VelocityOfAstronaut.
.912kg*12m/s=66kg*v2
v2= .165281m/s
Velocity is distance divided by time, so time = distance/velocity.
45.3m/.165281m/s = 274s = 4.6min. According to the quest homework system, this answer is wrong. Please help!
 
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