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2 years ago

The speed limit on some interstate highways is roughly 90 km/h. (a) What is this in meters per second

Physics

1 answer:

attashe74 [19]2 years ago

7 0

Answer:

25 m/s

Explanation:

⠀⠀⠀⇒ Speed = 90 km/h

⠀⠀⠀⇒ Speed = 90 km/60 min [As 1 hr = 60 min]

⠀⠀⠀⇒ Speed = (90 × 1000) m/(60 × 60)sec

⠀⠀⠀⇒ Speed = 90000 m/3600 sec

⠀⠀⠀⇒ Speed = 900 m/36 sec

⠀⠀⠀⇒ Speed = 300 m/12 sec

⠀⠀⠀⇒ Speed = 100 m/4 sec

⠀⠀⠀⇒ Speed = 25 m/s

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3 years ago

Una rapidez de 7 mm/us es igual a: A) 7000m/s B) 70 m/s C) 7 m/s D) 0.07 m/s

Ivan

For this conversion you should know that 1 meter has 1000 millimeters and that 1s equals 1000000 micro seconds, then:

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3 years ago

The spherical side mirror on a car is convex and has a radius of curvature of 25 cm. Another car is following, 20 m behind the m

svlad2 [7]

Answer:

(D) 0.99 cm

Explanation:

Given that the radius of curvature of the mirror is 25 cm.

And another car is following which is behind the mirror of 20 m.

$u=20m=2000cm$

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Now the mirror formula.

$1/v+1/u=1/f$

So,

$1/v+1/2000=-1/(25/2)\\1/v=-1/2000-1/12.5\\v=-12.422cm$

Now

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So,

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3 years ago

If a ball is rolling across a floor at a constant speed is it accelerating

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If it's curving left or right, then that's acceleration.

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3 years ago

Describe a situation that includes no less than four charges of any magnitude, but they combine so that another location, p, has

Degger [83]

Answer:

Four charges of equal magnitude sitting at the vertices of a square

Explanation:

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2 years ago