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givi [52]
3 years ago
7

A motorist is traveling at 20 m/s. He is 60 m from a stoplight when he sees it turn yellow. Is reaction time, before stepping on

the brake, is 0.50 s. What steady acceleration (slowing down) while braking will bring him to a stop right at the light?
Physics
1 answer:
Gnesinka [82]3 years ago
5 0
V₀ = V₁ + 2ax
V₀ = final velocity which is 0 m/s
V₁ = initial velocity which is 20 m/s
x = distance which is 60-(0.5 x 20) =50m
     this is because his reaction time is 0.5 sec so he traveled 10m before stepping on the break paddle.

a= (V₀-V₁) / 2x
  = (0-20) / 2*50
  = -0.2m/s
the negative is because it is a deceleration speed hence it is 0.2m/s
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Answer:

d = 5.75m

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r = \sin^{-1}\frac{n_1\sin i}{n_2}

r = \sin^{-1}\frac{(1)\sin (90-26.56)}{1.33}\\\\r = 42.26m

\tan r = \frac{2.5}{d_1}

d_1 = \frac{2.5}{\tan (42.26)} \\\\d_1 = 2.75m

Therefore, the distance is

d = 3 + d₁

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Index fossils are used to determine the relative ages of rock and fossils and are also used to
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Index fossils are used to determine the relative ages of rock and fossils and are also used to define the boundaries between geologic periods.

<u>Option: A</u>

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Answer:

Hey mate.....

Explanation:

This is ur answer...

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7 0
2 years ago
A 7 kg ball is moving at a constant speed of 5 m/s. A force of 300 N is applied to the ball for 4 s. The new speed of the ball i
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Answer:

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Explanation:

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