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Sholpan [36]
2 years ago
8

Can someone explain it with steps?

Physics
2 answers:
Yakvenalex [24]2 years ago
8 0
  • Initial velocity=15m/s=u
  • Final velocity=0
  • deacceleration=a

Distance traveled during reaction time

  • 15(0.4)=6m

Total distance

  • 21-6-1=14m

\\ \sf\longmapsto v^2-u^2=2as

\\ \sf\longmapsto -(15)^2=2(14)a

\\ \sf\longmapsto -225=28a

\\ \sf\longmapsto a=-8.0m/s^2

Anton [14]2 years ago
5 0

Answer:

Option C is the correct answer

Explanation:

Distance travelled by car during reaction time

=15\times0.4\\\\=6m

The car stopped before hitting the animal by 1 m

Distance travelled during deceleration is 21-6-1=14m

Hence by v^2=u^2+2as

We have

0^2=15^2+2 \cdot a \cdot 14\\\\a=\frac{-225}{28} \\\\=-8.03m/s^2

Option C is the correct answer

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