Which of the four observatories you explored had the worst light pollution?

a- mcdonald observatory
b- mauna kea
c- kitt peak national
d- griffith

Awoman stands a distance d from a loud motor that emits sound uniformly in all directions. the sound intensity at her position is an uncomfortable 2.0×10-3 w/m2. at a distance 2.6 times as far from the motor, what are (a) the sound intensity and (b) the sound intensity level relative to the threshold of hearing?

22. the effect of threshold braking is to a cause skids. b. lock wheels. c. prevent locking of wheels. d. increase stopping distance.

Does work output exceed work input when a machine is used? a) yes, it does, as machines create energy. b) it depends on the type of machine used. c) no, it doesn’t, as machines are inefficient. d) no, it doesn’t, as machines cannot create energy.