Problem $1(75$ points total$)$

This problem consists of $15$ multiple$-$choice questions. For each question, circle only one

answer; no explanation is required.

Scoring: $5$ points for each correct answer, no partial credit

Questions $1-5$ :

Driving on a highway a $30($m$)/($s$),$Grant$5\mathrm{.}5($m$)/($s$^(2)).$ during which time he

travels a distance of $130$ m $.$ Then he slams on his brakes, decelerating at a

rate of $(5\mathrm{.}0($m$)/($s$^(2)))$w hile $($skidding $200$ m $)$

$($d$)/($t$)1.$ For how long does Grant accelerate?

$($a$)3\mathrm{.}32$sB$,\{($:$[$ Rate $]),($d$=130$m$)$:$\}$

$($d$)4\mathrm{.}33$si$,-130=(-55$m$($m$)/($sec$))+(1)/(12)($a$)(30($m$)/($s$))^(2)$

$($c$)5\mathrm{.}45$s$,-130=(5\mathrm{.}5($m$)/($sec$))+450(9)$

What is hisspeed at the end of his deceleration? $(130-5\mathrm{.}5($m$)/($sec$))/(450)=129\mathrm{.}9$

$($a$)30\mathrm{.}0($m$)/($s$)$A$,200$ms

$($d$)0($m$)/($s$)$

$30\mathrm{.}0$ms$-0($m$)/($sec$)=30\mathrm{.}0($m$)/($sec$)$

$($a$)3\mathrm{.}01$s

$($b$)6\mathrm{.}02$s

$($d$)8\mathrm{.}94$ s C

$($d$)10\mathrm{.}8$ s

t$=?$

$200$m$=(1)/(2)(50($m$)/($sec$^(2)))$t

$(200)/(25)=(25$t$)/(25),$t$^(2)=8$

What is Grant's average velocity during his time in motion $($including both the acceleration

and deceleration segments$)?(35\mathrm{.}3($m$)/($s$)()/())/(($vec$($v$)))=(\backslash$Delta r$)/(\backslash$Delta t$),(200($m$)-30($m$))/(5\mathrm{.}5($m$)/($sec$^(2)-5\mathrm{.}0($m$)/(5)$ec$^(2)))=70$s$,$

$($b$)24\mathrm{.}1($m$)/($s$)$

$146\mathrm{.}0$

$($c$)22\mathrm{.}5($m$)/($s$)$

$($d$)15\mathrm{.}0($m$)/($s$)$

For the deceleration segment of Grant's motion, which of the following statements i$($s$)/($a$)$re

true?

$($a$)$ His displacement and velocity are in opposite directions. B

$($b$)$ His displacement and acceleration are in opposite directions.

$($c$)$ Both $($a$)$ and $($b$)$

$($d$)$ Neither $($a$)$ nor $($b$)$