Acylindrical space colony 8km in diameter and 30 km long hasbeen proposed as living quarters for future space explorers. such a habitat would have cities, land and lakes on the insidesurface and air and clouds in the center. all this would beheld in place by the rotation of the cylinder about the longaxis. how fast would such a cylinder have to rotate toproduce a 1-g gravitational field at the walls of thecylinder?
a) 0.05 rad/s
b) 0.10 rad/s
c) 0.15 rad/s
d) 0.20 rad/s
e) 0.25 rad./s

A.

Explanation:

To solve this problem it is necessary to take into account the concepts related to angular velocity and centripetal acceleration,

from the cinematic equations of motion we know that

where,

V = Tangential Velocity

r = radius

Angular velocity

While the centripetal acceleration is given by

The displacement of the object is based on gravitational acceleration, so

a = g = 9.8 and the radius would be

Reemplazando:

Therefore the answer is A.

heat the gas and measure the pressure

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form