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Pavel [41]
3 years ago
8

PHYSICS PLEASE HELP!

Physics
1 answer:
Salsk061 [2.6K]3 years ago
3 0

Answer:

It would take two half-lives which would be 130days

The substance has a half-life of 30 minutes. There has been two cycles that have occurred.

idk the last one

Explanation:

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A TV satellite dish is designed to receive radio waves of wavelength
Verizon [17]

Answer:

4.7 GHz

Explanation:

Applying,

v = λf................. Equation 1

Where v = velocity of the radio wave, λ = wavelength, f = frequency

make f the subject of the equation

f = v/λ.............. Equation 2

Note: A radio wave is an electromagnetic wave, as such it moves with a velocity of 3.00 x 10⁸ m/s

From the question,

Given: λ = 0.0644 meters

Constant: v = <em>3.00 x 10⁸ m/s</em>

Substitute these values into equation 2

f = (3.00 x 10⁸)/0.0644

f = 4.66×10⁹ Hz

f = 4.7 GHz

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3 years ago
What makes a good scientific question? (1 point)
liraira [26]

C. It is answered by observation and evidence.

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Two identical balls are thrown vertically upward. the second ball is thrown with an initial speed that is twice that of the firs
Temka [501]
The motion of the ball on the vertical axis is an accelerated motion, with acceleration 
a=g=-9.81 m/s^2
The following relationship holds for an uniformly accelerated motion:
2aS=v_f^2 - v_i^2
where S is the distance covered, vf the final velocity and vi the initial velocity.

If we take the moment the ball reaches the maximum height (let's call this height h), then at this point of the motion the vertical velocity is zero:
v_f =0
So we can rewrite the equation as
2(-9.81 m/s^2) h=-v_i^2
from which we can isolate h
h= \frac{v_i^2}{19.62} (1)

Now let's assume that v_i is the initial velocity of the first ball. The second ball has an initial velocity that is twice the one of the first ball: 2v_i. So the maximum height of the second ball is
h= \frac{(2v_i)^2}{19.62}= \frac{4v_i^2}{19.62} (2)

Which is 4 times the height we found in (1). Therefore, the maximum height of ball 2 is 4 times the maximum height of ball 1.
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What happens when you see something?
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Two double bonds means that the total number of electrons being shared in the molecule is
torisob [31]

One double bond consists 4 electrons, so 2 double bonds means 8 electrons

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