Astronaut Brian leaves Earth in a spaceship at a speed of 0.280c relative to an observer on Earth. Brian is holding a pencil at an angle of 30.0 with the direction of travel, as seen by Brian.
What angle does the pencil make with the direction of travel, as seen in the frame of reference of the observer? A) 29.0
B) 30.0
C) 31.0
D) 32.0
E) 33.0
Question 2
An irreversible engine operating between the temperatures of 550 K and 300 K extracts 1200 J of heat from the hot reservoir and produces 450 J of work. How much entropy is created in the process?
A) 0.32 J/K
B) 0.68 J/K
C) 0.44 J/K
D) 0.73 J/K
E) 0 J/K
Nitrogen content of live and dead leaves
Astronomers identified 12-billion-year-old white dwarf stars only 100 light years away from Earth
Eucalyptus tree leaves
Evidence that Light Travels at a Finite Speed
Benvenuto Cellini, Saltcellar: Neptune (Sea) and Tellus (Earth).
Escape Speed Problem