Which of the choices describes an action–reaction force pair for a space station containing astronauts in orbit about the earth?

(a) the weight of the astronauts and the centripetal force on the space station.
(b) the weight of the space station and the centripetal force on the space station.
(c) the weight of the astronauts and the gravitational force of the space station on the astronauts.
(d) the weight of the space station and the gravitational force of the space station on the earth.

(D) The weight of the space station and the gravitational force of the space station on the earth.

Explanation:

In both A and B , both the forces act in the same direction ( downwards ) , so they can not be action- reaction force .

In the option C , weight of a astronaut can only be reaction force of gravitational force exerted on the earth by astronaut. Both astronaut and the earth pull each other with equal and opposite force.  So option D is correct.

(D) The weight of the space station and the gravitational force of the space station on the earth.

Explanation:

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west