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2 years ago

10

How far can a person run in 15 seconds if she runs at an average speed of 160 cm/s? State your answer in meters.

1 answer:

uysha [10]2 years ago

8 0

Answer: distance = 24 meters

Explanation:

speed = distance / time

distance = speed x time

speed = 160 cm/s = 1.6 m /s [ 100 cm = 1 m, 160 cm = 1.6 m ]

time = 15 s

distance = 1.6 m/s x 15 s = 24 m

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${\mathfrak{\underline{\purple{\:\:\: Given:-\:\:\:}}}} \\ \\$

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${\mathfrak{\underline{\purple{\:\:\:To \:Find:-\:\:\:}}}} \\ \\$

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☯ As we know that,

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$\dashrightarrow\:\: \sf{ {v}^{2} = {u}^{2} + 2as }$

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$\dashrightarrow\:\: \sf{ \bigg(\dfrac{v}{2} \bigg)^{2} = {v}^{2} + 2a s_{1}}$

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$\dashrightarrow\:\: \sf{{0}^{2} = {v}^{2} + 2 \times \dfrac{ - 25 {v}^{2} }{2} \times s }$

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$\dashrightarrow\:\: \sf{ s_{2} = 0.04 - 0.03 }$

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$\star\:\sf{Left \: penetration \: before \: it \: come \: to \: rest \: is \:{\bf{ 1 \: cm}}} \\$

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