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Homework Help: Traffic Accident

  1. May 2, 2006 #1
    boy knocked down by van at pedestrian crossing with lights. point of impact was 4.6 km from kerb.there was a witness.
    boy said- i crosse imm green man came on.thought van would stop
    driver said - i was travelling at 40 k/h .light was green .i slammed brakr imm. but still hit him.at no more than 10k/h
    witness said i was behind boy .boy walked quickly as green man came on

    the witness was asked to walk 5m several times at same pace as boy when crossind. average time was 2.9s. slight injury to boy impact speed most 10 k/h.
    4 skid marks longest 19.8m. coeff of tyre/road friction was 0.76.phasing for lights- yellow light lasted 3s before green man and the red light came on together

    1. dist van travel after impact?
    2. dist travelledfrom braking to impact
    3.speed of van before braking
    4. average speed while braking
    5. stopping time
    6time elapsing between impact and stopping
    7.time passing between start of braking and impact
    8. reaction time of driver
    9.what time between seeing the boy and impact
    10.boys reaction time after seeing light turn green
    11.dist boy stands from the kerb
    12.dist boy walks before impact
    13.time taken for this walk

    have tried most but would like to check answers
  2. jcsd
  3. May 2, 2006 #2


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    We won't do your work and certainly won't take pay-outs. Show us some work and we can help.
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