SOLUTION: After landing on the moon, Apollo astronauts used a carlike vehicle called the lunar rover to explore the moon´s surface. For safety, they had to stay within walking distance of th

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Question 937831: After landing on the moon, Apollo astronauts used a carlike vehicle called the lunar rover to explore the moon´s surface. For safety, they had to stay within walking distance of their spacecraft in case the rover broke down.
How far could the Apollo astronauts drive away from their spacecraft at 10 km/h and still be able to walk back at 2.5 km/h, if their spacesuits could sustain life for 8 hours ?

Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
d = max exploration distance from spacecraft
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s = d/t
t = d/s
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time needed to drive from spacecraft to distance d
t = d/s
a = d/10
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time needed to walk from distance d to spacecraft
t = d/s
b = d/2.5
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assume they leave the spacecraft and drive in a straight line to distance d, and upon reaching distance d the rover breaks and they immediately walk back to the spacecraft:
a + b = 8
d/10 + d/2.5 = 8
2.5d + 10d = 8*(2.5*10)
d = 8*(2.5*10)/12.5
d = 16
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answer:
d = 16 miles
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if they do anything other than drive straight to d, the above calculation is wrong. for example, if they get off the rover to collect rocks, and then drive 16 miles away from the spacecraft, and the rover breaks, they will die!
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