The answer is a meteor.
Meteors make flashing light when they enter the Earth's atmosphere. This is actually meteors on fire, because our atmosphere makes them burn when they come in contact, and crashes them under the pressure. This makes up for a beautiful sight on the night sky, and people often refer to the burning meteors as ''falling stars'', and make wishes as well.
Answer:
0.027 cubic ft/min
Explanation:
Volume of water is V=V(t) Depth of water is h=h(t)
The relationship between V and h is
V=π/3.r2.h
Let
h0= the height of the cylinder = 24ft, r0= the radius of the opening = 10ft.
Since water level (h) rise with respect to flow rate we find an expression for r and substitute into V
r/h = r0/h0= 10/24 = 5/12
r = (5/12) h,
Substitute for r in V
so,
V=1/3.π.(h2)square = 1/3.π. 25/144.(h3)
When
h= 16ft
and dV/dt = 20ft3/min
,
dV/dt =1/3*π*25/144*h3*(dh/dt)
20ft3/min= 1/3*π* 25/144*h3*(dh/dt)
20 = 1/3*π*(16)3.(dh/dt)
Make dh/DT subject of formula
dh/dt=(20*3*144)/(25*π*4096) = 8640/321740.8
=
dh/dt= 0.027 ft3/min
The time it takes for 1g of strontium-90 to decay to 250 mg is; 57.6 years
<h3>What is the half life of an element?</h3>
The formula for half life is;
A(t) = A₀ * (¹/₂)^(t/t_1/2)
Where;
A(t) is amount left after t years
A₀ the initial quantity of the substance that will undergo decay;
t_1/2 is the half-life of the decaying quantity.
We are given;
t_1/2 = 28.8 years
A₀ = 1 g
A(t) = 250 mg = 0.25 g
Thus;
0.25 = 1 * (¹/₂)^(t/28.8)
log 0.25 = (t/28.8) log (1/2)
-0.60206 = (t/28.8) * -0.3010
t = 2 * 28.8
t = 57.6 years
Read more about half life at; brainly.com/question/11152793
Answer:
He said that science wasn't constantly approaching the truth.
Explanation:
Thomas Kuhn had a very different view when it came to science. Hope I have helped.