Average speed is total distance divided by total time.
Total distance is 50 m + 150 m + 300 m = 500 m
Total time is 68 s + 35 s + 22 s = 125 s
Average speed is 500 m / 125 s = 4 m/s
Answer:
The answer is aluminum foil.
<u>Answer:</u>
Pyrite leaves behind a green-black streak when it is rubbed against an unglazed porcelain plate as a part of the streak test process.
<u>Explanation:</u>
Different minerals produce different coloured streaks when rubbed against a white ceramic or porcelain streak plate. This streak test is done to identify the mineral and distinguish the same from other minerals that look similar in colour and texture.
It must be ensured that the test is done on clean and fresh specimens of the mineral and that there must be no contaminants. Pyrite specimens are usually brass-yellow colour but it leaves a green-black streak when the streak test is done.
(a) The speed of light in the unknown substance is determined 1.82 x 10⁸ m/s.
(b) The light will bend away from the normal since speed of light in air is not equal to speed of light in the substance.
<h3>What is the speed of light?</h3>
The speed of light passing from air into the substance is calculated as follows;
refractive index = speed of light in air / speed of light in the substance
speed of light in the substance = speed of light in air/refractive index
speed of light in the substance = (3 x 10⁸) / (1.65)
speed of light in the substance = 1.82 x 10⁸ m/s
Thus, the light will bend away from the normal since speed of light in air is not equal to speed of light in the substance.
Learn more about speed of light here: brainly.com/question/104425
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