, 08.11.2019 09:31 natpiink

# A) the current theory of the structure of the earth, called plate tectonics, tells us that the continents are in constant motion. assume that the north american continent can be represented by a slab of rock 5900 km on a side and 26 km deep and that the rock has an average mass density of 2800 kg/m^3. the continent is moving at the rate of about 4 cm/year. what is the mass of the continent. answer in units of kg. b) what is the kinetic energy of the continent? answer in units of kg. c) a jogger (of mass 80 kg) has the same kinetic energy as that of the continent. what would his speed be? answer in units of m/s.

### Another question on Physics

Physics, 21.06.2019 22:50
As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is 100) a) static friction. b) kinetic friction. c) a combination of static and kinetic friction. d) neither static nor kinetic friction, but some other type of friction. e) it is impossible to tell what type of friction acts in this situation.
Physics, 22.06.2019 03:40
Aprojectile is launched from ground level with an initial velocity of v 0 feet per second. neglecting air​ resistance, its height in feet t seconds after launch is given by s equals negative 16 t squared plus v 0 t. find the​ time(s) that the projectile will​ (a) reach a height of 192 ft and​ (b) return to the ground when v 0equals112 feet per second. ​(a) find the​ time(s) that the projectile will reach a height of 192 ft when v 0equals112 feet per second. select the correct choice below​ and, if​ necessary, fill in the answer box to complete your choice.