Which of the following materials is a good conductor of electric current?
a. a light bulb filament
b. a glass pane
c. a silver spoon
d. a rubber tire

Ateam of astronauts is on a mission to land on and explore a large asteroid. in addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. with what minimum initial speed vesc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? assume that the asteroid is approximately spherical, with an average density p 3.84 x108 g/m3 and volume v 2.17 x 1012 m3 recall that the universal gravitational constant is g 6.67 x 10-11 n m2/kg2

Aknife blade is a(n) a. lever b. screw c. wedge d. inclined plane

The most important difference between a wedge and an inclined plane is a. their size b. their shape c. how they are used d. what they are made of