Question 1106615: This is driving me crazy:
If the red car is traveling at 45 mph, and the blue is braking so that v(t) = 60-30t, then when will they pass each other, assuming that they are 10 miles apart at t=0?
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website!
If the red car is traveling at 45 mph, and the blue is braking so that v(t) = 60-30t, then when will they pass each other, assuming that they are 10 miles apart at t=0?
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Assuming t is in seconds and the blue cars speed is in mi/hr, and the blue car remains stationary after it's stopped:
60 - 30t = 0
t = 2 seconds.
Its avg speed for 2 seconds = 30 mi/hr = 44 ft/sec --> it moves 88 feet.
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The red car moves at 45 mi/hr = 66 ft/second. In 2 seconds it moves 132 feet.
--> after 2 seconds there 10*5280 - 220 feet apart = 52580 feet
52580/66 = 796.667 seconds from when they're 10 miles apart.
No idea when that is.
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Too many assumptions, IMO.
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