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egoroff_w [7]
3 years ago
15

The private papers of what scientist had to be decontaminated for two years in the 1990's before being put on file at the Nation

al Library in Paris? 577 points
Physics
1 answer:
SashulF [63]3 years ago
3 0
The answer is Marie Skłodowska Curie (AKA Marie Curie). She <span>lived her life awash in ionizing radiation. She would be carrying bottles of the radium and polonium in the pocket of her coat and put them in her desk drawer. 
So even after a century, her papers are still radioactive. Since the</span><span> most general isotope of radium, which is radium-226, has a half life of 1,601 years.</span>
You might be interested in
Please help ASAP!!
inessss [21]

Answer:

at t=46/22, x=24 699/1210 ≈ 24.56m

Explanation:

The general equation for location is:

x(t) = x₀ + v₀·t + 1/2 a·t²

Where:

x(t) is the location at time t. Let's say this is the height above the base of the cliff.

x₀ is the starting position. At the base of the cliff we'll take x₀=0 and at the top x₀=46.0

v₀ is the initial velocity. For the ball it is 0, for the stone it is 22.0.

a is the standard gravity. In this example it is pointed downwards at -9.8 m/s².

Now that we have this formula, we have to write it two times, once for the ball and once for the stone, and then figure out for which t they are equal, which is the point of collision.

Ball: x(t) = 46.0 + 0 - 1/2*9.8 t²

Stone: x(t) = 0 + 22·t - 1/2*9.8 t²

Since both objects are subject to the same gravity, the 1/2 a·t² term cancels out on both side, and what we're left with is actually quite a simple equation:

46 = 22·t

so t = 46/22 ≈ 2.09

Put this t back into either original (i.e., with the quadratic term) equation and get:

x(46/22) = 46 - 1/2 * 9.806 * (46/22)² ≈ 24.56 m

4 0
3 years ago
What is formula for time and velocity
Juliette [100K]
Divide distance by the time it takes to travel that distance
the formula for time is divide distance/speed
4 0
3 years ago
Cubes have sides of equal lengths. What is the fastest way to measure the volume of a cube-shaped table?
natima [27]
Measure the length of one side and then cube the answer. So if x represents the measurement of one side, x³ will give you the volume.
4 0
3 years ago
Which is a device that stores electric charge by separating positive and negative charges?
mafiozo [28]
Pretty sure its a capacitor
5 0
3 years ago
Read 2 more answers
Solve this system of equations without graphing and show your reasoning <br><br> 5x+y=7<br> 20x+2=y
tatuchka [14]

Answer:

Explanation:

5x + y = 7

20x - y = -2

    25x = 5

        x = (1/5)

5(1/5) + y = 7

1 + y = 7 .

y = 6

8 0
3 years ago
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