Under some circumstances, a star can collapse into an extremely dense object made mostly of neutrons and called a neutron star. the density of a neutron star is roughly 10^14 times as great as that of ordinary solid matter. suppose we represent the star as a uniform, solid, rigid sphere, both before and after the collapse. the star's initial radius was "9.0 x 10^5 km" (comparable to our sun); its final radius is 16 km.
part a) if the original star rotated once in 35 days, find the angular speed of the neutron star.

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.