Answer:
I think its 12 cm itself. Because in the question it is said that the length is same in all temperature
Maintaining an orbit has nothing to do with the satellite's speed.
ANY (tangential) speed is enough to stay in orbit, if the satellite
just stays away from Earth's atmosphere.
If the satellite completely stops moving 'sideways' at all, and just
hangs there, then the forces of gravity between the satellite and
the Earth will pull them together ... the satellite will fall into the
atmosphere and then to the ground.
Say we have a cylinder
that has a height of dx, we see that the cylinder has a volume of: <span>
<span>Vcylinder = πr^2*h = π(5)^2(dx) = 25π dx
Then, the weight of oil in this cylinder is:
Fcylinder = 50 * Vcylinder = (50)(25π dx) = 1250π dx.
Then, since the oil x feet from the top of the tank needs to
travel x feet to get the top, we have:
Wcylinder = Force x Distance = (1250π dx)(x) = 1250π x dx.
<span>Integrating from x1 to x2 ft gives the total work to be: (x1
= distance from top liquid level to ground level; x2 = distance from bottom
liquid level to ground level)</span>
<span>W = ∫ 1250π x dx
<span>W = 1250π ∫ x dx
W = 625π * (x2 – x1)</span></span></span></span>
<span>x2 = 14 ft + 15 ft = 29 ft</span>
x1 = 14 ft + 1 ft = 15
ft
<span>
W = 625π * (29^2 - 15^2)
<span>W = 385,000π ft-lbs
= 1,209,513.17 ft-lbs</span></span>
It protects us by keeping ultraviolet out and make sure everything lives
