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hjlf
2 years ago
12

When the driver of a car travelling at 36km/h suddenly sees a pedestrian in front of a car, he applies the brakes. The reaction

time of the driver is 0.2s. If the maximum deceleration that the brakes can produce is 20ms, find the maximum stopping distance for the car.​
Physics
1 answer:
egoroff_w [7]2 years ago
4 0

Answer:

144

Explanation:

36x0.2=7.2

7.2x20=144

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andrey2020 [161]

As long as it sits on the shelf, its potential energy
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If it falls from the shelf and lands on the floor, then it has exactly that
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Divide each side by  1.5 kg :     23.52 m²/s² = speed²

Take the square root of each side:    speed = √(23.52 m²/s²) =  <em>4.85 m/s </em> (rounded)


6 0
3 years ago
A wave with a wavelength of 0.1 m moves with a speed of 0.5 m/s. What is the frequency of the wave?
kondaur [170]
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The answer would be letter D.
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4 years ago
Which best describes why Keplers observation of planetary motion is a law instead of a theory
svet-max [94.6K]

Kepler's first law - sometimes referred to as the law of ellipses - explains that planets are orbiting the sun in a path described as an ellipse. An ellipse can easily be constructed using a pencil, two tacks, a string, a sheet of paper and a piece of cardboard. Tack the sheet of paper to the cardboard using the two tacks. Then tie the string into a loop and wrap the loop around the two tacks. Take your pencil and pull the string until the pencil and two tacks make a triangle (see diagram at the right). Then begin to trace out a path with the pencil, keeping the string wrapped tightly around the tacks. The resulting shape will be an ellipse. An ellipse is a special curve in which the sum of the distances from every point on the curve to two other points is a constant. The two other points (represented here by the tack locations) are known as the foci of the ellipse. The closer together that these points are, the more closely that the ellipse resembles the shape of a circle. In fact, a circle is the special case of an ellipse in which the two foci are at the same location. Kepler's first law is rather simple - all planets orbit the sun in a path that resembles an ellipse, with the sun being located at one of the foci of that ellipse.


5 0
3 years ago
Read 2 more answers
Which occurs when a wave is reflected?
dmitriy555 [2]

Answer: The wave can flip upside down.

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3 0
3 years ago
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Answer:

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a= -0.19m/s²

-a = 0.19m/s²

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5 0
2 years ago
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