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WITCHER [35]
3 years ago
11

. What is the atomic number for calcium?

Physics
1 answer:
zheka24 [161]3 years ago
8 0
20 is the atomic number for Calcium.
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If a cliff jumper leaps off the edge of a 100m cliff, how long does she fall before hitting the water? (assume zero air resistan
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<h2>Answer:</h2>

<em>Hello, </em>

<h3><u>QUESTION)</u></h3>

Assuming that the initial velocity of the jumper is zero, on Earth any freely falling object has an acceleration of 9.8 m/s².  

<em>✔ We have : a = v/Δt = ⇔ Δt = v/a </em>

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A snowball with a mass of 85 g hits the top hat of a 1.5 m tall snowman and sticks to it. the hat and the snowball, with a combi
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m1v1 + m2v2 = m3v3,

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Substituting;
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1.5 = 4.905*t^2
t = Sqrt (1.5/4.905) = 0.553 seconds

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Savanna regions developed during the Triassic period. is true
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