a student is speeding down route 11 in his fancy red Porschewhen his radar system warns him of an obstacle 400 ft ahead. heimmediately applies the brakes, starts to slow down and spots askunk in the road directly ahead of him. the "black box" in thePorsche records the car's speed every 2 seconds , producing thefollowing table. the speed decreases throughout the 10 seconds ittakes to stop, although not necessarily at a uniform rate. time since brakes applied (sec) 0 2 4 6 8 10 speed(ft/sec) 100 80 50 25 10 0 a) what is your best estimate of the total distance thestudent's car travelled before coming to rest? b) which one of the following statements can you justify fromthe information given? 1) the car stopped be

a student is speeding down route 11 in his fancy red Porschewhen his radar system warns him of an obstacle 400 ft ahead. heimmediately applies the brakes, starts to slow down and spots askunk in the road directly ahead of him. the "black box" in thePorsche records the car's speed every 2 seconds , producing thefollowing table. the speed decreases throughout the 10 seconds ittakes to stop, although not necessarily at a uniform rate. time since brakes applied (sec) 0 2 4 6 8 10 speed(ft/sec) 100 80 50 25 10 0 a) what is your best estimate of the total distance thestudent's car travelled before coming to rest? b) which one of the following statements can you justify fromthe information given? 1) the car stopped be

Question
a student is speeding down route 11 in his fancy red Porschewhen his radar system warns him of an obstacle 400 ft ahead. heimmediately applies the brakes, starts to slow down and spots askunk in the road directly ahead of him. the "black box" in thePorsche records the car's speed every 2 seconds , producing thefollowing table. the speed decreases throughout the 10 seconds ittakes to stop, although not necessarily at a uniform rate.
time since brakes applied (sec) 0 2 4 6 8 10
speed(ft/sec) 100 80 50 25 10 0
a) what is your best estimate of the total distance thestudent's car travelled before coming to rest?
b) which one of the following statements can you justify fromthe information given?
1) the car stopped before getting to the skunk.
2) the " black box" data is inconclusive. the skunk may or maynot have been hit.
3) the skunk was hit by the car.

Answers (1)

2020-12-25
(a)time since brakes applied (sec) 0 2 4 6 8 10
speed(ft/sec) 100 80 50 25 10 0
since the speed is dcreasing so it is a decreasing function.then lower estimation of the distance is
=[ 80+50+25+10+0](2) =330 feet
and upper estimation of the distance is
=[100+80+50+25+10](2) = 530 feet
we can find the best estimation of the distance by taking theaverage of these estimations
that is the best estimation of the distance is = (330+530)/2 =430 feet
(b) since 430 > 400 then the skunk was hit by the car
0

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