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steposvetlana [31]
3 years ago
7

The stopping sight distance for a car traveling at 50 mph is 461 ft (including both perception-reaction distance and braking dis

tance). The perception-reaction time is 2.5 sec. If a car traveling at 60 mph is to stop in the same distance with the same deceleration, what is most nearly the required perception-reaction time
Physics
1 answer:
Ivan3 years ago
4 0

Answer:

2.08 s

Explanation:

We are given that

Speed,v=50mph=73.3ft/s

1 mile=5280 feet

1 hour=3600 s

Distance,d=461 ft

t=2.5 s

v'=60 mph=88 ft/s

We have to find the perception reaction time.

Perception reaction distance=d_p=vt=73.3\ti es 2.5=183.25 feet

d_p=d'_p

d'_p=v't

t'=\frac{183.25}{88}=2.08 s

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A vw beetle goes from 0 to 60 mi/h with an acceleration of 2.35 m/s^2.
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Part a.
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v = 60 mi/h, the final velocity
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Note that
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Use the formula
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Part b.
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6 0
3 years ago
Add the vectors:
Anettt [7]

Vector 1 has components

x_1=(10\,\mathrm m)\cos20^\circ\approx9.40\,\mathrm m

y_1=(10\,\mathrm m)\sin20^\circ\approx3.42\,\mathrm m

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y_2=(10\,\mathrm m)\sin80^\circ\approx9.85\,\mathrm m

Add these vectors to get the resultant, which has components

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y_{\rm total}\approx13.268\,\mathrm m

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Answer:

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p₂ = 0

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