when I jump and land on the surface I exerts a force on the surface and the surface should exert the same amount of force on me, therefore I should be jumping again according to the 3rd law of motion but I don't why is that

The earth remains in orbit around the sun due to the force of gravity. how does the force of gravity exerted by the sun on the earth compare to the force of gravity exerted by the earth on the sun?

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Aperson walks first at a constant speed of 4.89 m/s along a straight line from point a to point b and then back along the line from b to a at a constant speed of 2.95 m/s. what is the average speed over the entire trip?