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RRmy0440
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Homework Statement
A space person is motionless a distance of 500m away from the safety of the spacecraft . The person has exactly 11.32min of air left and the person's mass is 103.2kg, including equipment. The person throws a phaser at a velocity of 50.2km/h away from the spacecraft in order to get back. I f the mass of the phaser is 5.3 kg, how many minutes of extra air does the person have when they get back to the spacecraft ?(Ans: 0.28min)
I attempted to solve it , but get the answer of 0.25min.
please help!
T
Homework Equations
Conservation and momentum.
P=mv
Ft=mv
Impulse momentum theory
The Attempt at a Solution
① m1v1+m2v2=m1v1'+m2v2'
v1'=42.97m/min
②t=500/(836.9m/min+42.97m/min) =0.57min
③d=v1't=42.97m/min *0.57min=24.42m
④d(remaining)=500m-24m=475.6m
⑤t=d/v=475.6m/ (42.97m/min)=11.07min
⑥t(remaining)=11.32-11.07=0.25min
I try to solve the question, but got the wrong answer. Could anyone help me out? Thank you so much.