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Physics chase problem help

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  • #1
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Physics chase problem help!!

Hi, i'm having a lot of difficulty with my physics homework. I'd really appriciate it if someone would help me out here :D

Homework Statement


Karan is driving at 90 km/h on a straight road at night, when she sees a skunk cross the road 60.0m ahead of this car. It takes him 0.25s to react before he puts on the brakes and decelerates at -5.00m/s2. Meanwhile, the skunk obliviously walks across the 5.00m wide road at 0.70 m/s. Calculate whether
a) Karan stops in time before she hits the skunk
b) the skunk crosses the road before Karan get there; or
c) Karan squishes the skunk

Homework Equations


I've just been given basic kinematics equations.
With variables v, d, t, a

The Attempt at a Solution


I'm not sure how to start answering this question.
 

Answers and Replies

  • #2
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0


The obvious first step is to convert all into SI system i.e km/hr to m/s..etc

from here there is a 2 way approach..

go with karan or skunk

for karan...

find time taken to reach at 60meter from origin
then use time to find whether the skunk manages to crosses
if skunk just reaches then it is crushed
if skunk dosent reach then karan is faster
if skunk reaches and travels more then it reaches faster

for skunk...

find time taken to cross the road
then compute whether karan travels less than 60 m or more in given time

if more then karan crosses first
if less then skunk passes first
if equal then god save the skunk

here it is assumed that karan travels along opp edge of 5.00 m wide road from where skunk starts walking

hope it helps
 
  • #3
4
0


The obvious first step is to convert all into SI system i.e km/hr to m/s..etc

from here there is a 2 way approach..

go with karan or skunk

for karan...

find time taken to reach at 60meter from origin
then use time to find whether the skunk manages to crosses
if skunk just reaches then it is crushed
if skunk dosent reach then karan is faster
if skunk reaches and travels more then it reaches faster

for skunk...

find time taken to cross the road
then compute whether karan travels less than 60 m or more in given time

if more then karan crosses first
if less then skunk passes first
if equal then god save the skunk

here it is assumed that karan travels along opp edge of 5.00 m wide road from where skunk starts walking

hope it helps
Thanks a lot it did help managed to solve the question :D I'm not sure if its right but yea!!
 

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