Segmented mirrors sag under their own weight. Their optical shape must be controlled by computer-driven thrusters under the mirrors in what is called
a. an achromatic lens.
b. active optics.
c. a Schmidt-Cassegrain design.
d. a Newtonian design.
e. interferometry.
Question 2
If the stars at the turnoff point of a cluster have a mass of 3 M, what is the age of the cluster?
a. 3.0 x 1010 years
b. 3.3 x 109 years
c. 6.4 x 108 years
d. 1.6 x 1011 years
e. The age of a star cluster can not be determined from the mass of stars at the turnoff point.
Optical Illusions
This pediatric growth chart tracks the height and weight for girls ages 2–20.
To increase pressure using body weight, lean on your client.
Overhead stretch for the shoulder muscles. Lean back to create the stretch using your body weight.
A very thin uniform rod, 2.40 m long and of weight 135 N, has a frictionless hinge at its lower ...
Comparing uncontrolled and controlled energy release.