Question

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Answer 1

a) is just a velocity = distance/time question

Answer 2

13.04

Answer 3

good

acceleration = (final velocity - initial velocity)/time = >

Answer 4

that would be m?

Answer 5

like 13.04m?

Answer 6

keep in mind what the question is asking for to determine what the units would be

Answer 7

m/s

Answer 8

"how long does it take" what are the units?

Answer 9

s?

Answer 10

good, it is asking for time so the units must be in time, so seconds

Answer 11

and for b) acceleration = (final velocity - initial velocity)/time --> plug the values in

Answer 12

(3.1)/3

Answer 13

it's final velocity - initial velocity using the velocity from a) as the initial velocity

Answer 14

(3.1-13.04)/3

Answer 15

13.04 is the time not the initial velocity

Answer 16

oh hold on , I'm screwing it up

Answer 17

(3.1-4.6)/13.04

Answer 18

use the time from part b) in the denominator not the time from part a)

Answer 19

(3.1-4.6)/3

Answer 20

good, and that equals..?

Answer 21

-0.5

Answer 22

good, so -0.5 m/s/s

Answer 23

okay so for c

Answer 24

you are given initial velocity, final velocity, and distance, which equation should we use to find the acceleration? note that you are not given time

Answer 25

4

Answer 26

good, now solve for a

Answer 27

initial velocity =4
distance=2

Answer 28

yes, keep going

Answer 29

4^2=2+2(a)x

Answer 30

delta x is the distance

if he is coming to a stop what must the final velocity be?

Answer 31

good, so

0^2 = 4^2 + 2a(2)

Answer 32

./..

Answer 33

-4

Answer 34

good, so -4 m/s/s is your answer

Answer 35

for d) use kinematics equation 3 to find the distance

Answer 36

x=3.1(1.5)+1/2(-4)t

Answer 37

using the initial velocity, acceleration, and time given in d)

Answer 38

x=3.1(1.5)+1/2(a)t

Answer 39

isn't it 3.1 and 1.5

Answer 40

"accelerates from rest"

what is the initial velocity?

Answer 41

good, now plug in deltax = v_o * t + (1/2)at^2 using the time and acceleration given in problem d)

Answer 42

;'';'

Answer 43

deltax=0*1.5+(1/2)a(1.5)^2

Answer 44

don't forget to plug in a

Answer 45

deltax=0*1.5+(1/2)(3.1)^2

Answer 46

t^2 is still 1.5^2

Answer 47

just plug in a = 3.1 while leaving everything else as it was

Answer 48

deltax=0*1.5+(1/2)(3.1)(1.5)^2

Answer 49

good, now solve for delta x

Answer 50

3.49

Answer 51

good so 3.49 m