Science:Math Exam Resources/Courses/MATH100/December 2016/Question 11 (b)

MATH100 December 2016
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Question 11 (b)

${\displaystyle A}$ and ${\displaystyle B}$, two people of identical height ${\displaystyle h}$, stand beneath a street lamp of height ${\displaystyle L}$. ${\displaystyle A}$ walks in a straight line and at a constant speed away from the street lamp. One second later, ${\displaystyle B}$ walks in a straight line and at the same speed, but in the opposite direction, away from the street lamp. As ${\displaystyle A}$ and ${\displaystyle B}$ move away from the lamp, their shadows grow longer.

(b) As ${\displaystyle A}$ and ${\displaystyle B}$ walk away from the lamp, both their shadows are getting longer. Whose shadow is changing length faster, two seconds after ${\displaystyle A}$ left the lamp? Justify your answer.

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