Answer:
a.14 s
b.70 s
Explanation:
a.Let the sidewalk moving in positive x- direction.
Speed of sidewalk relative to ground=[tex]v_s=1m/s[/tex]
Speed of women relative to sidewalk=v=1.5m/s
The speed of women relative to the ground
[tex]v_w=v_s+v=1+1.5=2.5m/s[/tex]
Distance=35 m
Time=[tex]\frac{distance}{speed}[/tex]
Using the formula
Time taken by women to reach the opposite end if she walks in the same direction the sidewalk is moving=[tex]\frac{35}{v_w}=\frac{35}{2.5}=14s[/tex]
b.If she gets on at the end opposite the end in part (a)
Then, we take displacement negative.
Speed of sidewalk relative to ground=[tex]v_s=1m/s[/tex]
Speed of women relative to sidewalk=v=-1.5 m/s
The speed of women relative to the ground=[tex]v_w=v_s+v=1-1.5=-0.5m/s[/tex]
Time=[tex]\frac{-35}{-0.5}=70 s[/tex]
Hence, the women takes 70 s to reach the opposite end if she walks in the opposite direction the sidewalk is moving.
