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Dmitrij [34]
3 years ago
9

Falling objects drop with an average acceleration of 9.8 m/sec/sec, or 9.8 m /s2. If an object falls from the top of a tall buil

ding, how long will it take before it reaches a speed of 49 m/sec?
Physics
1 answer:
Lena [83]3 years ago
5 0

Use the velocity expression for uniform acceleration and solve for t: v = v0 + at. v0 is zero since the object is at rest. 49 m/s = a(t), and solve for t. t = 49 m/s / 9.8 = 5 seconds.

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Find the given attachment

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A falling stone is at a certain instant 90 feet above the ground. two seconds later it is only 10 feet above the ground. if it w
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The equation relevant to this is:

S(t) = So + Vot - At²/2 <span>

</span>

<span>Therefore we can create two equations:
<span>S(t) = 90 = So - 4t - 16.1t²                                      --> eqtn  1</span>
<span>S(t+2) = 10 = So - 4(t+2) - 16.1(t+2)²                     --> eqtn 2</span>

</span>

<span>Expanding eqtn 2:
10 = So - 4t - 8 - 16.1(t² + 4t + 4) 
10 = So - 4t - 8 - 16.1t² - 64.4t - 64.4 
10 + 8 + 64.4 = So - 68.4t - 16.1t² 
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 <span>
Subtracting eqtn 1 by eqtn 3:</span>

 90 = So - 4t - 16.1t² 

82.4 = So - 68.4t - 16.1t²

 

=> 7.6 = 64.4t

t = 0.118 s

 

Therefore calculating for initial height So:<span>

<span>82.4 = So - 68.4(0.118) - 16.1(0.118)²

<span>So = 90.7 ft</span></span></span>

7 0
3 years ago
At a constant pressure, the volume of a gas doubles when the temperature in kelvins doubles. This is a statement of which gas la
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Boyle’s law and,Charles’s law

Explanation:

For a fixed mass of gas at constant pressure, the volume is directly proportional to the kelvin temperature. That means, for example, that if you double the kelvin temperature from, say to 300 K to 600 K, at constant pressure, the volume of a fixed mass of the gas will double as well.

6 0
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Read 2 more answers
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AfilCa [17]

C

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However, weight is an absolute SI unit and does not vary from experiment to experiment. It is, therefore, a non-biased variable to use in the experiment and determine which wood between oak and maple can hold more weight.

4 0
4 years ago
What is the charge on an object that experiences a force of 5 Newtons in an electric field of 50 Newtons per coulomb?
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Answer:

Explanation:

F = qE

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q is the test charge

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5=q(50)\\q=1*10^-^1Coulombs

6 0
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